Sirian partnered with Rissa while the guards fanned out around them, one alert while the other four paired up to spar.
Uzel, with the majority of students, regards the paired organs as mandibles and the unpaired as an epipharynx.
Hinds believe that the paired piercers are the inner lobes of the maxillae, and the unpaired piercer the left mandible, the right mandible being absent.
There are two main theories: (I) that the chromosomes which finally separate are at first paired side by side (Allen, Grgoire, Berghs, Strasburger and others), and (2) that they are joined together or paired end to end (Farmer and Moore, Gregory, Mottier and others).
(3) The os entoglossum originally paired, but coalescing into an arrow-headed piece, attached to the anterior end of the basihyal and lodged in the tongue proper.
Sometimes the ventral portions of these pads form paired or un paired little ossifications, then generally described as intercentra; such are not uncommon on the tail.
Dorsal vertebrae frequently have a ventral outgrowth of the centrum; these hypapophyses may be simple vertical blades, I-shaped, or paired knobs; they serve for the attachment of the thoracic origin of the longus collianticus muscle, reaching their greatest development in Sphenisci and Colymbidae.
Omitting the paired tracheo-clavicular muscles, we restrict ourselves to the syringeal proper, those which extend between tracheal and bronchial rings.
The ventral region of the thoracic skeleton is complex, each segment usually possessing a median sternum with paired episterna (in front) and epimera (behind).
The well-known "fire-flies" of the tropics are large click-beetles (Elateridae), that emit light from paired spots on the prothorax and from the base of the ventral abdominal region.
After eating the contents of the egg, the larva moults and becomes a fleshy grub with short legs and with paired spiracles close to the dorsal region, so that, as it floats in and devours the honey, it obtains a supply of air.
Biisgen that the sweet secretion (honey-dew) of the aphids is not derived, as generally believed, from the paired cornicles on the fifth abdominal segment, but from the intestine, whence it exudes in drops and is swallowed by the ants.
In any case the cavity of the prostomium is single, and not formed, as is the cavity of the segments of the body, by paired coelomic chambers.
Among the simpler Chaetopoda the coelom retains the character of a series of paired chambers, showing the above relations to the exterior and to the gonads.
Though the paired arrangement of the nephridia is the prevalent one in the Chaetopoda, there are many examples, among the Oligochaeta, of species and genera in which there are several, even many, nephridia in each segment of the body, which may or may not be connected among themselves, but have in any case separate orifices on to the exterior.
Tomopteris is remarkable for the fact that the hammer-shaped prostomium has paired ventral processes each with a single seta.
Nephridia generally paired, often very numerous in each segment, in the form of long, much-coiled tubes with intracellular lumen.
It is not quite certain whether these are to be regarded as the remnant of an earlier excretory system, replaced among the Oligochaeta by the subsequently developed paired structures, or whether these "head kidneys" are the first pair of nephridia precociously developed.
In any case the nephridia which occupy the segments of the body generally are first of all represented by paired structures, the "pronephridia," in which the funnel is composed of but one cell, which is flagellate.
The paired disposition of these organs is the prevalent one among the Oligochaeta, and occurs in all of twelve out of the thirteen families into which the group is divided.
In the genera Pheretima, Megascolex, Dichogaster, &c., each segment contains a large number of nephridia, which, on account of the fact that they are necessarily smaller than the paired nephridia of e.g.
In any case they have been shown in three genera to develop by the growth and splitting into a series of original paired pronephridia.
A complex network, however, does occur in Lybiodrilus and certain other Eudrilidae, where the paired nephridia possess ducts leading to the exterior which ramify and anastomose on the thickness of the body wall.
The spermathecae are usually paired structures, one pair to each of the segments where they occur.
Nephridia always paired and without plexus of blood capillaries.
Nephridia always paired, rarely (Pontobdella) forming a network communicating from segment to segment; lumen of nephridia always intracellular, funnels pervious or impervious.
Paired setae of Oligochaetous pattern present in anterior segments.
17, d), we find right and left of the two renal apertures a right and left gillplume or ctenidium, which here as in Haliotis and Pleurotornaria retain their original paired condition.
RHIPIDOGL0ssA.-Aspidobranchia with a palliovisceral anastomosis (dialyneurous); eye-vesicle closed, with crystalline lens; ctenidia, osphradia and hypobranchial glands paired or single.
Of any kind; a short evaginable pharynx, bearing paired conical buccal appendages or " cephalocones."
This paired organ consists of a string of cells which are perforated by a duct opening to the exterior and ending internally in a flame-cell.
The origin of the paired arteries from the PrGabp 1 ._.
- Diagrams of the development and adult structure of one of the paired central eyes of a scorpion.
Asp, Paired anterior process of the subneural arch.
DR, The paired dorsal ridges.
An important feature is the occurrence in some species (Ptychoderidae) of paired longitudinal pleural or lateral folds of the body which are mobile, and can be approximated at their free edges so as to close in the dorsal surface, embracing both the median dorsal nerve-tract and the branchial grooves with the gill-pores, so as to form a temporary peri-branchial and medullary tube, open behind where the folds cease.
The nervous system is represented by an oesophageal collar and a suboesophageal ganglion, whence paired nerves pass outwards to innervate the anterior extremity and backwards towards its posterior end.
The sternum has no keel, and ossifies from lateral and paired centres only; the axes of the scapula and cora.coid have the same general direction; certain of the cranial bones have characters very unlike those possessed by the next order - the vomer, for example, being broad posteriorly and generally intervening between the basisphenoidal rostrum and the palatals and pterygoids; the barbs of the feathers are disconnected; there is no syrinx or inferior larynx; and the diaphragm is better developed than in other birds.'
The paired oviducts and vasa deferentia are, as we have seen, mesodermal in origin.
Palmen (1884) on these ducts have shown that in may-flies and in female earwigs the paired mesodermal ducts open directly to the exterior, while in male earwigs there is a single mesodermal duct, due either to the coalescence of the two or to the suppression of one.
The series of paired spiracles on most of the trunk-segments is well displayed, as a rule, in terrestrial larvae - caterpillars and the grubs of most beetles, for example.
But the pupa hangs from the surface by means of paired respiratory trumpets on the prothorax, the dorsal thoracic surface, where the cuticle splits to allow the emergence of the fly, being thus directed towards the upper air.