Renal Sentence Examples

There may be from one to nine gills between the genital and renal pores.

The renal organs are tubular outgrowths of the pericardial parts of the coelom; the reproductive cells are derived from cells lining the generative portion.

The largest pair of branchiae is placed immediately behind the renal openings and corresponds to the single pair of other molluscs, the organs being repeated anteriorly only (Metamacrobranchs) or anteriorly and posteriorly (Mesomacrobranchs).

The renal tube is doubled on itself, its middle part where the bend occurs being situated more or less anteriorly.

A simple gonaduct on each side arises from the gonad near its posterior end and passes first forwards, then backwards, and lastly outwards to the external opening in the pallial groove, anterior to the renal aperture.

The coelom differs from that of the Chitons in the fact that the cavities of the genital organs are continuous with it, and in the fact that there is only one pair of coelomoducts resembling the renal organs of Chitons, but serving also as genital ducts.

On this view then the Aplacophora are more primitive than the Polyplacophora in the relations of coelom, gonad and coelomoducts; and the genital ducts of the Chitons have arisen either by metameric repetition within the group, or by the gradual loss of an original connexion between the generative sac and the renal tube, as in Lamellibranchs and Gastropods, the generative sac acquiring a separate duct and opening to the exterior on each side.

In small or moderate doses it is a powerful diuretic. Though Heidenhain asserts that rise in the renal blood-pressure has not a diuretic action per se, it seems probable that this influence of the drug is due to a rise in the general blood-pressure associated with a relatively dilated condition of the renal vessels.

In large doses, on the other hand, the renal vessels also are constricted and the amount of urine falls.

In pain due to violent sciatica relief and even permanent cure has been obtained by the injection of morphine directly into the muscle of the affected part, and in the treatment of renal and hepatic colic morphine given subcutaneously will relieve the acute pain consequent on the passage of biliary and urinary calculi.

The effect of large doses is to cause great pain in the renal region and urgent wish to micturate.

It must not be employed in cases of renal disease, owing to the risks attendant upon absorption.

The toxic symptoms have already been detailed, the patient usually dying from arrest of the renal functions.

The renal organs of the oyster were discovered by Hoek to agree in their morphological relations with those of other lamellibranchs.

The genital opening on each side is situated in a depression of the surface into which the renal organ also opens.

The most important excretory or renal organs of the Crustacea are two pairs of glands lying at the base of the antennae and of the second maxillae respectively.

The renal organs are a pair of short wide sacs with folded walls lying on either side of the anterior end of the liver.

Tubes of renal excretory function in a like position occur in most terrestrial Arthropoda - viz.

Such renal caecal tubes seem to be readily evolved from either metenteron or proctodaeum when the conditions of the out-wash of nitrogenous waste-products are changed by the transference from aquatic to terrestrial life.

The absence of such renal caeca in Limulus and their presence in the terrestrial Arachnida is precisely on a parallel with their absence in aquatic Crustacea and their presence in the feebly branchiate Amphipoda.

Renal caecal tubes (Malpighian tubes) open into the proctodaeum.

Renal excretory caeca (Malpighian tubes) are developed from the proctodaeum (not from mesenteron as in scorpion and Amphipoda).

It thus appears that in Peripatus the coelom does not develop a perivisceral portion, but gives rise only to the renal and reproductive organs.

In some people not being able to make the urine acid called renal tubular acidosis makes calcium phosphate stones more likely.

Salicylate appears to competitively inhibit plasma protein binding of acetazolamide and simultaneously to inhibit acetazolamide renal secretion that may produce serious metabolic acidosis.

Chronic renal failure is amenable to dietary modification however acute is not.

Since the renal allograft has no collateral arterial supply, irreversible injury may result if the ischemic time exceeds 1.5 hours.

The second most common type, accounting for 6-20% of renal stones, is formed from struvite (magnesium ammonium phosphate ).

Neurological storage disease has been reported in this breed and renal amyloidosis, a form of kidney disease, has also been seen.

A renal angiogram helps to diagnose narrowed blood vessels to the kidney.

Possible causes of an abscess would include appendicitis, Crohn's disease, diverticular disease of the caecum, renal infection,?

This in turn decreases the resistance in the afferent arteriole which results in an increase in renal blood flow.

In addition to promoting systemic atherosclerosis, an elevation in lipid levels also may contribute to the development of glomerulosclerosis in chronic renal failure.

Obstruction or rupture of the urinary tract distal to the renal pelvis will result in a post-renal azotemia.

The systemic bioavailability of omeprazole is not significantly altered in patients with reduced renal function.

Ibandronic acid is eliminated by renal excretion only and does not undergo any biotransformation.

A study was to investigating whether the use of cardiopulmonary bypass increased the risk of developing acute renal failure.

She is currently based at Great Ormond Street Hospital where she is doing an MD on vascular calcification in children with end-stage renal disease.

A Phase III trial in renal cell carcinoma is planned to start in 2006.

Since the renal clearance of imatinib is negligible, a decrease in total body clearance is not expected in patients with renal insufficiency.

The staff in A&E thought he had renal colic again, supported by the presence of traces of blood in his urine.

Perhaps the use of ' sulphuric ether ' for renal or biliary colic was recognized earlier than 1842.

Renal cell carcinomas can present with ' clot ' colic similar in nature to ureteric colic due to renal calculus.

It is used to treat pain of renal colic.

It is relatively contraindicated in asthma and renal failure and should be given in small increments in uncorrected hypovolaemia.

The medulla is full of renal tubules, but does not contain renal corpuscles.

The renal corpuscles are always found in the renal cortex.

Serum urea and electrolytes and creatinine to assess renal function (but a normal serum creatinine does not rule out obstruction ).

Low albumin and high creatinine can indicate renal involvement.

The outcome was development of end stage renal disease or doubling of serum creatinine.

Will show dilatation of the renal pelvis suggesting reflux or obstruction.

By contrast, there were no unfilled posts in renal medicine or infectious diseases.

Concurrent administration of potent diuretics, aminoglycosides may adversely affect renal function (see section 4.4 ).

The tumors of the bilateral epididymis were surgically resected and of the right renal tumor enucleated.

Production of endogenous erythropoietin is impaired in patients with chronic renal failure and the primary cause of their anemia is due to erythropoietin deficiency.

Anemia commonly results from chronic renal failure, but can be easily treated with injections of the hormone erythropoietin.

The kidneys are badly injured which can lead to chronic renal failure.

Ensure appropriate renal function - monitoring urine output is normally easiest.

Patients may present with life-threatening renal failure due to rapidly progressive glomerulonephritis requiring urgent dialysis and immunosuppression.

Renal disease is characteristic and the typical histological appearance is a focal segmental necrotising glomerulonephritis.

The young male with ' primary ' gout is frequently overweight, a heavy beer drinker, with no family history of renal disease.

Diagnosis Thrombosis of the aorta and aortic graft Renal infarction Discussion The more distal images demonstrated the nature of his previous surgery.

In patients with chronic renal failure the mean terminal half-life was found to be 19.5 hours.

Zarontin should be used with caution in patients with impaired hepatic or renal function.

Patients were also screened for normal hepatic and renal functions.

Dosing in children with impaired renal and/or hepatic function has not been studied.

A proportion of Lupus nephritis patients in endstage renal failure still require immunosuppression.

Evaluation of patients with post-myocardial infarction should always include assessment of renal function.

Acute renal failure This may occur with any serious illness or operation, particularly those complicated by severe infection.

Experimental work shows that losartan (tho not its active metabolite) competitively inhibits urate reabsorption in the renal proximal tubule.

Probenecid can severely inhibit renal excretion of methotrexate, and so is contraindicated.

Risk factors for the development of hyperkalaemia include renal insufficiency, potassium sparing diuretics and the concomitant use of agents to treat hypokalaemia.

Due to limited experience in patients with severe renal insufficiency, such patients should be treated with caution.

The resulting low cardiac output can cause hypotension, renal insufficiency and/or acute hepatic ischemia.

This is a dog kibble designed to support chronic renal failure in dogs.

The sonographic features of renal vein thrombosis include an enlarged kidney with absent venous flow on CDI or PD imaging [22] .

If renal failure is irreversible (a condition known as end stage renal failure or ESRF ), then long-term dialysis becomes necessary.

Renal lupus Lupus affecting the kidney is sometimes said to be the most severe lupus.

In addition, specialized products have been produced for patients with specialized nutrient requirements eg malabsorption, renal failure, cancer cachexia.

This minimizes the loss of urea from the renal medulla, and allows the concentration of urea in urine.

However use of these agents are not recommended below one year of age due to the possibility of immature renal function and hepatic metabolism.

Acute renal failure with acute tubular necrosis may develop even in the absence of severe liver damage.

Eleven selected only bladder carcinomas, four included all neoplasms of the urinary tract and one selected carcinomas of the renal pelvis and ureter.

On the other hand it is possible that many patients identified as having hypertensive renal disease actually have indolent nephritis.

The other 2, who presented 10 days after consumption of the mushrooms, developed severe interstitial nephritis and did not recover renal function.

Cases of interstitial nephritis have been reported which have sometimes resulted in renal failure.

His special areas of interest include renal physiology, vasculitis, dialysis and critical care nephrology.

This hypothesis is supported by the fact that only organisms that are able to stimulate neutrophils are associated with renal scarring.

For example, urinary tract obstruction, can be treated to save renal function.

Pax-2 is expressed in early kidney organogenesis, Wilms ' tumor and renal cell carcinoma.

The lesion displays heterogeneous texture with echogenicity similar to the normal renal parenchyma.

Kirsten's son's scan showed several ' soft markers ' for Downs, including a dilated renal pelvis.

Patients with poor renal function may require dosage adjustments due to altered pharmacokinetics of carboplatin.

In addition an extensive search was made for other studies relating to ace gene polymorphism and renal damage.

Because of their effect on renal prostaglandins, cyclo-oxygenase inhibitors such as naproxen can increase the nephrotoxicity of cyclosporin.

Almost any renal disease, or any type of renal injury, can cause proteinuria.

Nephritis ranges from asymptomatic proteinuria (presence of protein in the urine) to sudden onset of renal insufficiency.

Nephrotic level proteinuria usually requires renal biopsy to establish the cause, unless this is immediately evident.

The use of methotrexate high-dose regimens recommended for osteosarcoma requires meticulous care due to the potential for additive or synergistic renal toxicity.

However, renal function should be assessed and the dose should be reduced if there is evidence of severe renal insufficiency.

Dr. Dudley has a clinical interest in hypertension, renal disease and multisystem disorders and also renal complications of obstetrics.

There are other risks, tho, mainly renal failure and congestive heart failure.

This information is mostly about renal lupus - that is, lupus affecting the kidneys.

Discussion The number of unfilled posts in 1999 was surprisingly high, and only renal medicine and infectious diseases managed to fill all vacancies.

In acute renal failure fluid retention can lead to hyponatraemia.

Doctors from different specialities e.g. rheumatology, renal and dermatology will often look after one patient.

The renal clearance of salicylates is increased by corticosteroids and steroid withdrawal may result in salicylate intoxication.

The ' take-home ' message is always to look at renal activity on a skeletal scintigram.

It is probably also cleared by glomerular filtration, and can be used for renal scintigraphy.

In addition, renal tubular secretion of creatinine is increased at higher serum levels.

A number of imaging techniques can be used to diagnose renal artery stenosis, all with similar accuracy.

Renal artery stenosis is most common in older people.

There are over 100 patients receiving renal replacement therapy.

It was more in growing toenails than Renal transplants.

Recent studies have included people with treatment with schizophrenia, children with cystic fibrosis and adults with renal transplant.

These small molecules pass through the renal tube (coiled tubule) which is surrounded by a capillary network.

Kidney tissue The renal tubule is continuous with Bowman's capsule.

Horsfield's tortoises fed on cat or dog food frequently die from renal failure or from impacted bladder stones of solidified urates.

Urography Care should be exercised in patients with moderate to severe impairment of renal function (as reflected by a raised blood urea ).

Blood chemistry including electrolytes, liver function and renal function were normal except for high uric acid and metabolic acidosis.

Renal function parameters, especially urinary output should be monitored after the examination in these patients.

There are no renal organs with a wide intercellular lumen, such as occur in the Polychaeta, nor is there ever any permanent association between nephridia and ducts connected with the evacuation of the generative products, such as occur in Alciope, Saccocirrus, &c. In these points the Oligochaeta agree with the Hirudinea.

Thus the renal organ of Aplysia is shown to conform to the Molluscan type.

When examined with the microscope, by means of the usual section method, they are seen to consist of a labyrinthine tube lined with peculiar cells, each cell having a deep vertically striated border on the surface farthest from the lumen, as is seen in the cells of some renal organs.

Cushny has shown experimentally that slowing of the blood-flow through renal tissue causes less sodium chloride to appear in the urine while the excretion of urea and sulphates remains unaffected; apparently the chloride, being more permeable, is reabsorbed and so only appears to be excreted in less quantity.

A good case for the examination of the question as to whether blood enters the pericardium of Lamellibranchs, or escapes from the foot, or by the renal organs when the animal suddenly contracts, is furnished by the Ceratisolen legumen, which has red blood-corpuscles.

Retrograde pyelography revealed an irregular filling defect in the right renal pelvis.

The new renal unit and radiology suite will also be moved to the new hospital planned for north Norfolk.

Hence, there is no need to readjust the dosage in the presence of impaired renal function.

Neither of these agents should be used in patients with renal impairment.

In patients with chronic renal failure the mean terminal half life was found to be 19.5 hours.

Treatment should be discontinued at the time of renal transplantation.

Such changes in renal function may be reversible upon discontinuation of therapy.

A ribbon-cutting ceremony marked the completion of work on Southmead Hospital 's renal outpatients facility.

In the latter patient group, even a small increase in serum creatinine may be indicative of unilateral loss of renal function.

Renal function Normal, healthy kidneys are capable of filtering large amounts of calcium that is subsequently reclaimed by tubular reabsorption.

Kidney tissue The renal tubule is continuous with Bowman 's capsule.

Horsfield 's tortoises fed on cat or dog food frequently die from renal failure or from impacted bladder stones of solidified urates.

Urography Care should be exercised in patients with moderate to severe impairment of renal function (as reflected by a raised blood urea).

Many lab tests have been conducted, but authorities have yet to reach a firm conclusion about what may have caused acute renal failure-related deaths in both cats and dogs, making this Iams cat food recall a real mystery.

Polycystic Kidney Disease (PKD) - This is a genetically inherited, progressive kidney disease that eventually leads to renal failure.

Feline renal failure poses a serious risk to your cat's life.

It is important that you contact your vet or emergency animal care clinic immediately if you suspect your pet may be suffering from renal failure.

Feline renal failure simply means that your cat's kidneys are shutting down for some reason.

There are two types of renal failure in cats.

If untreated, acute renal failure can result in death in a very short time.

The prognosis for acute renal failure is usually not very good.

Some breeds have a higher rate of chronic renal failure than others, and this may indicate that genetics may be a contributing factor.

There are a few breeds that have a higher incidence of chronic renal failure than other breeds.

Researchers believe that there may be several factors that contribute to a cat developing renal failure.

This may cause imbalances and an inability for the body to absorb some nutrients; this can eventually cause renal failure.

Low potassium may cause renal failure over a period of time.

There seems to be a correlation between low potassium levels and the development of renal failure in cats.

There is no treatment for chronic renal failure.

Most cats, with proper treatment, can live several months and even up to a few years with renal failure.

Renal failure is not painful until the very last stages of the illness.

These contaminants can cause numerous health issues in cats and dogs including renal failure and death.

Results of cats consuming these foods include an imbalance of the pH in their urine, causing urinary tract disorders, renal failure and other problems.

Indian Rhubarb Root - Rhubarb root has a long history of use as a treatment for ulcers and for renal failure.

Tubule-Tissues and cells associated with the structures that connect the renal pelvis to the glomeruli.

The most common complications following repair surgery are postoperative renal failure and recoarctation.

Left untreated, however, those individuals who do develop amyloidosis of the kidneys may require a kidney transplant or may even die of renal failure.

Uncontrolled diabetes is a leading cause of blindness, end-stage renal disease, and limb amputations.

Renal artery stenosis-A disorder in which the arteries that supply blood to the kidneys are narrowed or constricted.

Children with renal disease often experience growth retardation, especially if the condition is congenital.

Rarely, malignant tumors of the kidney (renal cell carcinoma) occur within an existing angiolipoma.

Renal vein thrombosis develops when a blood clot forms in the renal vein, which is the blood vessel that carries blood from the kidneys back to the heart.

When one or more blood vessels in the kidneys become narrowed (renal artery stenosis) because of debris and plaque build-up, or blocked because of a blood clot (renal vein thrombosis), the kidneys are unable to function properly.

The onset of renal vein thrombosis can be rapid (acute) or gradual.

Blood clots in the renal arteries are uncommon, but when they do occur, there is a risk of pulmonary embolism, a dangerous condition that occurs when the clot or a portion of the clot dislodges and travels to the lungs.

Renal vein thrombosis occurs in both infants and adults.

The number of people who suffer from renal vein thrombosis is difficult to determine, as many do not show symptoms, and the disorder is diagnosed only by specific tests.

Ninety percent of pediatric cases of renal vein thrombi occur in infants less than one year old; 75 percent occur in infants under one month of age.

In children, most cases of renal vein thrombosis are thought to be caused by an episode of severe dehydration.

Renal vein thrombosis is more common in patients with nephrotic syndrome, although studies have shown high variability among these patients, with rates of 5 to 62 percent reported.

Acute onset of renal vein thrombosis at any age causes pain in the lower back and sides of the abdomen, fever, bloody urine, decreased urine output, and sometimes kidney failure.

A physician makes the diagnosis of renal vein thrombosis based on the presence of symptoms and the results of a medical examination and diagnostic tests.

He or she will also place the stethoscope over the child's abdomen; when renal vein thrombosis is present, the doctor may hear an abnormal "whooshing" as blood tries to flow through the blocked vessel.

A less common test used to diagnose renal vein thrombosis is renal venography, also called renal angiography, an x-ray examination of the renal veins after a contrast material (dye) has been injected.

This test may be performed to locate the narrowing or blockage in the renal vein.

One of the major goals of treatment is to prevent the blood clot in the renal vein from detaching and moving into the lungs (pulmonary embolism), where it can cause serious complications.

Clot-busting medications, such as tissue plasminogen activator (t-PA, also called streptokinase enzymes or thrombolytic drugs), may be given to help dissolve the renal clot.

If the renal artery is partially or completely blocked, an interventional catheter-based procedure may be performed.

Using renal angiography, doctors pinpoint the precise location of the blockage and deliver the medication to that spot.

In a renal endarterectomy, a vascular surgeon removes the blockage from the inner lining of the renal artery.

Bypass surgery reroutes the blood flow around the narrowed or blocked sections of the renal artery.

Rarely, when there is a complete blockage of the renal vein in infants, the kidney must be surgically removed.

Most cases of renal vein thrombosis resolve over time, without permanent injury to the kidneys.

Acute renal failure can occur with severe dehydration.

Death from renal vein thrombosis is rare, and is often caused by the blood clot detaching and lodging in the heart or lungs.

Renal vein thrombosis cannot be prevented.

Preventing dehydration by maintaining fluids in the body may help reduce the risk of renal vein thrombosis.

When a child has been diagnosed with renal vein thrombosis, it is important to follow the doctor's recommendations for follow-up checkups to closely monitor his or her condition.

Kidney infections, a narrowing of the arteries that carry blood to the kidneys, called renal artery stenosis, and other kidney disorders can disturb the salt and water balance.

In severe and acute (sudden-onset) cases, hypertension can cause seizures, swelling throughout the body, blindness, or renal (kidney) failure.

Maternal renal and cardiopulmonary disease and multiple gestation are factors in IUGR.

Decreased amniotic fluid (oligohydramnios) is associated with IUGR as the fetus may have a decreased cardiac output and thus decreased renal flow to produce less urine.

Tsuchiya, M., et al. "Ultrasound screening for renal and urinary tract anomalies in healthy infants."

Other common abnormalities include elbow deformities, abnormally shaped pelvis bone (hip bone), and kidney (renal) disease.

Kidney disease has been reported in children with nail-patella syndrome, but renal involvement more commonly develops during adulthood, usually during the fourth decade of life.

Children receiving kidney transplants do not develop nail-patella-type renal complications in their new kidney.

Survival among patients with nail-patella syndrome is not decreased unless they exhibit renal complications.

Black henna tattoos can cause significant allergies and rashes, leading to renal (kidney) failure and even death in those who are sensitive to their ingredients.

In some cases a renal biopsy may be useful to determine the extent of kidney involvement.

There is a higher likelihood of permanent renal damage with a higher number of recurrences.

Chronic renal failure and certain medications also can cause secondary deficiencies.

In its most serious form, complications can include high blood pressure (hypertension) and renal failure.

Other drugs that appear to interact negatively with kombucha are medications for hypertension, renal (kidney) problems, and hormone replacement medications.

It also covers certain disabled citizens who are under the age of 65 and people suffering from End-Stage Renal Disease, which is permanent kidney failure treated with dialysis or a transplant.

Disabled individuals under the age of 65, and people with end-stage renal disease (ESRD) are also eligible for coverage by Medicare, but the coverage benefits are more limited than those available to older individuals.

Medicare - Medicare is available not only for people over 65, but may be available for people with some disabilities, including end-stage renal disease.

It also covers younger people with disabilities in certain circumstances, as well as people who have End-Stage Renal Disease.

They are often associated with a host of serious conditions, including anemia, malnutrition, respiratory disease, renal failure and kidney problems.

There is no renal portal system, excepting unimportant vestiges of such a system in the head kidneys.

Close to this the small renal organ (i, mediad) and the larger renal organ (k, to the right and posteriorly) are seen, also the pericardium (1) and a coil of the intestine (int) embedded in the compact liver.

The existence of two renal organs in Patella, and their relation to the pericardium (a portion of the coelom), is important.

Each renal organ is a sac lined with glandular epithelium (ciliated cell, with concretions) communicating with the exterior by its papilla, and by ce, Cerebral ganglia.

Subsequent connected by nerve investigations carried on under the directo the streptoneur tion of the same naturalist have shown ous visceral loop. that the larger as well as the smaller renal sac is in communication with the pericardium.

The walls of the renal sacs are deeply plaited and thrown into ridges.

Below the surface these walls are excavated with blood-vessels, so that the sac is practically a series of blood-vessels covered with renal epithelium, and forming 6 Cephalic tentacle.

Near this and less advanced into the branchial chamber is the single renal organ or nephridium r with its opening to the exterior r'.

The heart c lying in the pericardium is seen in close proximity to the renal organ, and consists of a single auricle receiving blood from the gill, and of a single ventricle which pumps it through the body by an anterior and posterior aorta.

With regard to internal organization we may commence with the disposition of the renal organ (nephridium), the external opening of which has already been noted.

The typical character is retained by the heart, pericardium, and the communicating nephridium or renal organ in all Opisthobranchs.

There are no specialized sense-organs or vascular or respiratory systems. There is a wide body-cavity, but as this has no connexion with the renal or reproductive organs it cannot be regarded as a coelom, but probably is a blood-space or haemocoel.

Both belong to the category of " coelomoducts," namely, r- ' tubular or funnel-like portions of the coelom opening to the exterior in pairs in each somite (potentially,) and usually persisting in only a few somites as either "urocoels" (renal organs) or "gonocoels"(genital tubes).

Scorpio is here provided with a single or double pair of renal excretory tubes, which have been identified by earlier authors with the Malpighian tubes of the Hexapod and Myriapod insects.

Limulus agrees with the majority of the Crustacea in being destitute of renal excretory caeca or tubes opening into the hinder part of the gut.

It must be pointed out that the presence or absence of such renal excretory tubes opening into the intestine appears to be a question FIG.

In fact it is not possible to maintain that the renal excretory tubes of the gut are of one common origin in the Arthropoda.

It is invariably the result of some cause acting generally, such as renal disease, valvular defect of the heart, or an impoverished state of the blood; while a mere oedema is usually dependent upon some local obstruction to the return of blood or lymph, or of both, the presence of parasites within the tissue, such as the filaria sanguinis hominis or trichina spiralis, or the poisonous bites of insects.

Some other observers, however, have not got such good results with a chloride-free diet, and Marishler, Scheel, Limbecx, Dreser and others, dispute Widal's hypothesis of a retention of chlorides as being the cause of oedema, in the case of renal dropsy at all events; they assert that the chlorides are held back in order to keep the osmotic pressure of the fluid, which they assume to have been effused, equal to that of the blood and tissues.

Bainbridge suggests that a retention of metabolic products may cause the oedema in renal disease, Bradford having previously shown that loss of a certain amount of renal tissue caused retention of metabolic products in the tissues.

As sodium chloride is one of the most permeable of crystalloids it seems strange that damage to the renal tissue should impede its excretion.

Potassium salts are strongly diuretic, acting directly on the renal epithelium.

A pair of renal tubes opening right and left, rather far forward on the sides of the body, are always present.

A pair of genital apertures, connected by genital ducts with the paired gonads, are found right and left near the nephridial pores, except in a few cases where the genital duct joins that of the renal organ (Spondylus).

It, as in other Mollusca, is not a blood-space but develops from the coelom, and it communicates with the exterior by the pair of renal tubes.

The left inner gill-plate is also snipped to show the subjacent orifices of the left renal organ x, and of the genital gland (testis or ovary) y.

The blood makes its way by large veins to a venous sinus which lies in the middle line below the heart, having the paired renal organs (nephridia) placed between it and that organ.

The renal organs may be more ramified in other Lamellibranchs than they are in Anodonta.

From all parts of the pyriform sac narrow stalk-like tubes are given off, ending in abundant widely-spread branching glandular caeca, which form the essential renal secreting apparatus.

The glands secrete hippuric acid which passes from the pericardium into the renal organs.

In the most primitive Lamellibranchs there is no separate generative aperture but the gonads discharge into the renal cavity, as in Patella among Gastropods.

In Arca, in Anomiidae and in Pectinidae the gonad opens into the external part of the renal tube.

The next stage of modification is seen in Ostraea, Cyclas and some Lucinidae, in which the generative and renal ducts FIG.

The four orders now retained exhibit successive stages in the modification of the ctenidia by reflection and concrescence of the filament, but other organs, such as the heart, adductors, renal organs, may not show corresponding stages.

In them the foot has a flat ventral surface used for creeping, as in Gastropods, the byssus gland is but slightly developed, the pleural ganglia are distinct, there is a relic of the pharyngeal cavity, in some forms with a pair of glandular sacs, the gonads retain their primitive connexion with the renal cavities, and the otocysts are open.

Renal and genital apertures separate.

Gonads contained in the visceral mass and generally open into renal.

In the former the genital coelom and the pericardial coelom are continuous and the reproductive cells escape by the renal ducts.

Assuming that these ancestral forms resembled the existing Nautilus in their internal anatomy, they had two pairs of renal ducts and one pair of genital ducts, which would apparently indicate, not a single metamere or unsegmented body, but three metameres.

The Dibranchia, with only one pair of branchiae, one pair of renal organs, and one pair of genital ducts, are much more recent, not appearing till the end of the Secondary epoch, and therefore must be regarded as descended from the Tetrabranchia.

In the Dibranchia true nephridia have not been detected in the embryo, nor has it been shown that the genital ducts are derived from the renal tubes.

The last is between the pericardium and the foot; from it the blood passes through the renal organs to the ctenidia.

In some cases the coelom is formed as a single cavity, and renal and generative organs are formed from its walls.