CARAPACE. 



L 110 ] 



CARTILAGE. 



leaves, and P. Footii, Berk, and Desm., on 

 evergreens, the beech, and also on Mercurialis 

 perennis, but in this species the fruit has not 

 been observed. 



BiBL. Berk, and Desm. Trans. Hort. Soc. 

 iv. 243 ; Montague, Ann. Nat. Hist. 2 ser. 

 iii. 520. 



CARAPACE, or lorica. — A term some- 

 what indefinitely applied to the whole or a 

 part of the shell or outer coat of certain 

 animals ; as those belonging to the classes 

 Crustacea, Rotatoria, Infusoria, &c. 



In regard to the Rotatoria and Infusoria, 

 it has been divided into the testa or testula, 

 an envelope resembling that of the tortoise, 

 within which the body of the animal is in- 

 closed, the head and the tail being free : as 

 in the genera Brachionus, Monura, Colurus, 

 &c.; the scutellum, a round or oval envelope, 

 covering only the back of the animal, in the 

 manner of a buckler ; and the urceolus, a 

 membranous or firm envelope, sometimes 

 gelatinous, in the form of a bell or cylinder, 

 open at one end and closed at the other, and 

 within which the animal can completely 

 retract itself; as in Difflugia, &c. 



Ehrenberg extended the use of this term 

 also to the external envelope of Volvox, 

 Gonium and the Diatomacese. As these 

 have been removed to the vegetable kingdom, 

 it is not now applied to them. 



CARBONATE OF LIME. See Lime, 

 Carbonate of. 



CARBONIC ACID.— The presence of 

 this gaseous acid is usually determined by 

 the addition of another acid, as acetic or 

 muriatic, to the object under the microscope; 

 and if colourless and inodorous bubbles 

 escape, it is concluded, and in most cases 

 correctly, that carbonic acid is present. 



It must be borne in mind that if the object 

 be immersed in liquid, the gas may arise 

 either from this or the object ; for it is well 

 known that the escape of a gas from a liquid 

 charged with it, is greatly facilitated by the 

 presence of a solid and especially a pointed 

 body, and that the gas escapes from the 

 liquid at its surface or point ; thus the 

 false appearance is produced of the gas being 

 liberated from the body. Hence the import- 

 ance of washing the object before the addition 

 of the acid (Introduction, p. xxxvii). 



When crystalline bodies of different forms 

 are present, these must be separated before 

 the addition of the acid, otherwise the bubbles 

 liberated from those of one kind, by escaping 

 at the surface of the others, may give rise to 

 the false conclusion, that they were derived 

 from the former. 



Recollection of the fact that carbonic acid 



is readily absorbed by solution of potash, 

 would allow of the distinction of bubbles of 

 this acid from those of au*. 



BiBL. See Chemistry. 



CARCHESIUM, Ehr.— A genus of Infu- 

 soria, belonging to the family Yorticellina. 



Char. Pedicle branched, spirally flexible ; 

 bodies of the animals all alike (= branched 

 Vorticellce) . 



C. polypinum (PI. 23. figs, 20, 21). Body 

 conico-campanulate, colourless, broad and 

 truncate in front, margin prominent, pedicle 

 sub-umbellate ; aquatic ; length of body 

 1-580 to 1-430". 



Ehrenberg describes two other species, 

 C pygmceum and C. specfabile; these are, 

 however, probably not distinct. 



BiBL. Ehrenb. Infus. and Ber. d. Berl. 

 AJcad. 1840, p. 199; Dujardin, hifus. p. 551; 

 Stein, Infusionsthiere, p. 48, &c. 



CARIS, Latreille. — A doubtful genus of 

 Arachnida, of the order Acarina, and family 

 Gamasea. 



The single species, C. vespertilionis, is 

 found upon the bat {Vespertilio pipistrellce). 

 It is probably a young Dermanyssus. 



BiBL. Latreille, Gen. Crust ac. et Insect 

 i. p. 161 ; Audouin, Ann. d. Sc. nat. Zool. 

 xxv. p. 412; Walckenaer, Apteres (Gervais), 

 p. 227. 



CARMINE.— This beautiful pigment is 

 sometimes used to feed Infusoria and fill 

 their sacculi or gastric vesicles (Infusoria). 



It has also been used as a colouring 

 matter for injections. 



CARPAIS. See Gamasus. 



CARPOMITRA, Kiitz.— A genus of Spo- 

 rochnaceee (Fucoid Algse) containing one 

 rare British species, C. Cabrercp, Clem., re- 

 markable for the peculiar mitre-shaped con- 

 ceptacle containing the spores. 



BiBL. Harvey, Br. Marine Alg. pi. 5 B., 

 Phyc. Brit. pi. 14. 



CARTILAGE. — Cartilage consists of a 

 firm, but elastic, bluish, milky or yellowish 

 substance ; which morphologically forms 

 either a simple parenchyma composed of 

 cells, or a structure consisting of cells 

 immersed in an intermediate basis. 



The cells of cartilage are usually round, 

 oval, elongated or angular, frequently flat- 

 tened and sometimes spindle-shaped. In 

 some cartilage, they appear stellate, 

 as in that of the cuttle-fish, the sharks and 

 rays, and enchondromatous growths ; but it 

 has not been determined in these in- 

 stances whether they are really stellate, or 

 whether the stellate appearance arises from 

 the existence of secondary deposit within 

 cartilage-cells of the common forms (see 



