Shenstone, two classes are to be recognized: (I) Nataloins, which yield picric and oxalic acids with nitric acid, and do not give a red coloration with nitric acid; and (2) Barbaloins, which yield aloetic acid, C7H2N205, chrysammic acid, C 7 H 2 N 2 0 6, picric and oxalic acids with nitric acid, being reddened by this reagent.
Indicus, the largest of the genus, from the Malay Peninsula (as far north as Tavoy and Mergui), Sumatra and Borneo, distinguished by its peculiar coloration, the head, neck, fore and hind limbs being glossy black, and the intermediate part of the body white, the height at the shoulder from 3 ft.
The coloration is mostly beautiful, black and red.
Detection and Estimation.-Most calcium compounds, especially when moistened with hydrochloric acid, impart an orange-red colour to a Bunsen flame, which when viewed through green glass appears to be finch-green; this distinguishes it in the presence of strontium, whose crimson coloration is apt to mask the orange-red calcium flame (when viewed through green glass the strontium flame appears to be a very faint yellow).
EYRA (Felis eyra), a South American wild cat, of weasel-like build, and uniform coloration, varying in different individuals from reddish-yellow to chestnut.
With ferric chloride it gives a violet coloration, and with bromine water a white precipitate of tribromphenol.
The success of procryptic coloration depends, however, very largely upon stillness, and the instinct to keep stationary without moving a limb is a marked characteristic of all spiders unless engaged in hunting or fleeing from imminent danger.
A blue coloration indicates nitrogen, and is due to the formation of potassium (or sodium) cyanide during the fusion, and subsequent interaction with the iron salts.
It crystallizes in prisms which melt at 36° C. and boil at 201 0.8 C. It is soluble in water, and the aqueous solution gives a blue coloration with ferric chloride.
Laevis, the "smooth snake" of Europe, in England, in Hampshire and Dorsetshire, eats chiefly lizards; owing to its coloration, which varies much, it is often mistaken for the viper.
C. antiquorum, are characterized by the large frontal horn of the bulls, the white legs, the network type of coloration and the pale tint.
On this and other accounts the coloration of the sky is highly variable.
The molybdates may be recognized by the fact that they give a white precipitate on the addition of hydrochloric or nitric acids to their solutions, and that with reducing agents (zinc and sulphuric acid) they give generally a blue coloration which turns to a green and finally to a brown colour.
They form many double salts and give a dark violet coloration with ferric chloride solution, this colour, however, gradually disappearing on standing, sulphur being precipitated.
Colias, which is distinguished by a somewhat different pattern of coloration, the transverse black bands of the common mackerel being in this species narrower, more irregular or partly broken up into spots, while the scales of the pectoral region are larger, and the snout is longer and more pointed.
Some of the species of Aviculariidae also appear to be warningly coloured with black or black and red, and their coloration is associated with the urticating nature of their bristles, which makes them highly unpalatable to vertebrate foes.
Hence as a very general rule the coloration makes for concealment under natural conditions of existence, and the instincts which lead to concealment are very highly developed.
As instances of procryptic or celative coloration may be mentioned that of the species of the genus Dolomedes, one of the Lycosidae, which lives amongst reeds and is marked with a pair of longitudinal yellow lines which harmonize with the upright stalks of the vegetation, and Lycosa pitta, which lives on the sand, can scarcely be seen on account of its mottled pattern: Sparassus smargdulus and the species of Pecucetia, which are found amongst grass or low green herbage, are mostly green in colour, and Salticus scenicus is banded with white and black to match the grey tint of the rocks and stone walls on which it hunts its prey.
The extent to which procryptic coloration and instincts favouring concealment are developed indicates that generation after generation spiders have been subjected to persecution from enemies.
For example, when a solution of a ferric salt is added to a solution of potassium thiocyanate, a deep red coloration is produced, owing to the formation of ferric thiocyanate.
Its crimson flame-coloration was observed by C. G.
Another type of dry reaction, namely, the flame coloration, had been the subject of isolated notices, as, for example, the violet flame of potassium and the orange flame of sodium observed by Marggraf and Scheele, but a systematic account was wanting until Cartmell took the subject up. His results (Phil.
The flame coloration may give information as to which elements are present.
In the second group, we may notice the application of litmus, methyl orange or phenolphthalein in alkalimetry, when the acid or alkaline character of the solution commands the colour which it exhibits; starch paste, which forms a blue compound with free iodine in iodometry; potassium chromate, which forms red silver chromate after all the hydrochloric acid is precipitated in solutions of chlorides; and in the estimation of ferric compounds by potassium bichromate, the indicator, potassium ferricyanide, is placed in drops on a porcelain plate, and the end of the reaction is shown by the absence of a blue coloration when a drop of the test solution is brought into contact with it.
Beilstein determines their presence by heating the substance with pure copper oxide on a platinum wire in the Bunsen flame; a green coloration is observed if halogens be present.
Sulphur is detected by heating the substance with sodium, dissolving the product in water, and adding sodium nitroprusside; a bluish-violet coloration indicates sulphur.
The coat is shaggy and oily, and is preferred with as little white as possible, but the general black coloration may have rusty shades.
The Dalmatian or coach dog (sometimes called the plumpudding dog) is a lightly built pointer, distinguished by its spotted coloration, consisting of evenly disposed circular black spots on a white ground.
The reagents in common use are: Millon's reagent, a solution of mercuric nitrate containing nitrous acid, this gives a violet-red coloration; nitric acid, which gives a yellow colour, turning to gold when treated with ammonia (xanthoproteic reaction); fuming sulphuric acid, which gives violet solutions; and caustic potash and copper sulphate, which, on warming, gives a red to violet coloration (biuret reaction).
Von Wrangel); the various coloration of many animals according to the composition of the forests they inhabit (the sable and the squirrel are well-known instances); the intermingling northern and southern faunas in the Amur region and the remarkable consequences of that intermixture in the struggle for existence; - all these render the study of the Siberian fauna most interesting.
In coloration it bears some resemblance to a chaffinch, but its much larger size and enormous beak make it easily recognizable, while on closer inspection the singular bull-hook form of some of its wing-feathers will be found to be very remarkable.
It is volatile (para-oxybenzaldehyde is not) and gives a violet coloration with ferric chloride.
Both the two former are iron-grey on the upper parts, and black below, a style of coloration rare among mammals, as the upper side of the body is in the great majority darker than the lower.
This, when adult, is readily distinguishable from the ordinary bird by the absence of the blush from its plumage, and by the curled feathers that project from and overhang each side of the head, which with some difference of coloration of the bill, pouch, bare skin round the eyes and irides give it a wholly distinct expression.
It is a colourless oily liquid which boils at 225°-227° C., is somewhat soluble in water, and does not give a coloration with ferric chloride.
Owing to impurities contained in the materials from which glasses are made, accidental coloration or discoloration is often produced.
For currants and raisins, both produced by varieties of the grape-vine, see the respective articles.] Apart from their economic value, vines are often cultivated for purely ornamental purposes, owing to the elegance of their foliage, the rich coloration they assume, the shade they afford, and their hardihood.
The coloration is generally sombre, but to this there are exceptions; the fruit-bats are brownish yellow or russet on the under surface; two South American species are white; Blainville's chin-leafed bat is bright orange; and the Indian painted bat (Cerivoula pieta) with its deep orange dress, spotted with black on the wing-membranes, has reminded observers of a large butterfly.
The coloration of tsetse-flies is sombre and inconspicuous; the brownish or greyish-brown thorax usually exhibits darker longitudinal markings, and when the insect is at rest the abdomen or hinder half of the body is entirely concealed by the brownish wings.
Their coloration consists often of bright hues, and sometimes resembles that of their surroundings.
Its coloration varies from pale golden brown to black; the scales are smooth and shiny.
American genus Urotheca bear an extraordinary resemblance in coloration to the pretty, black, red and yellow poisonous Elaps.
A still more remarkable resemblance exists in the shape and striking, red, black and yellow coloration between Scolecophis aemulus of Chihuahua and the poisonous Elaps fulvius, the American coral-snake, but Cope has been careful to point out that these two creatures are not known to inhabit the same district.
A more delicate method consists in adding a very little anthraquinone and sodium amalgam; absolute alcohol gives a green coloration, but in the presence of minute traces of water a red coloration appears.
Traces of bismuth may be detected by treating the solution with excess of tartaric acid, potash and stannous chloride, a precipitate or dark coloration of bismuth oxide being formed even when only one part of bismuth is present in 20,000 of water.
Butterflies, moths and bees are very abundant, the former being remarkable for their size and splendid coloration; but these groups have not been investigated exhaustively enough to afford a correct idea of their number or their true affinities.
2 More extraordinary than this, from one point of view, is the great variety of coloration that obtains in these temporary outgrowths.
Analysis, &c. - All volatile potassium compounds impart a violet coloration to the Bunsen flame, which is masked, however, if sodium be present.
They present great diversities of size, length and thickness of fur, and coloration, although resembling each other in all important structural characters.
Similar instances of protective coloration could be cited without end.
Ammonia and ammonium salts can be readily detected, in very minute traces, by the addition of Nessler's solution, which gives a distinct yellow coloration in the presence of the least trace of ammonia or ammonium salts.
Sodium is most distinctly recognized by the yellow coloration which volatile salts impart to a Bunsen flame, or, better, by its emission spectrum which has a line (double), the Fraunhofer D, line, in the yellow (the wave-lengths are 5896 and 5890).
It will not thrive in rivers; in large ponds it readily reverts to the coloration of the original wild stock.