CHYLE. 



[ 174 ] 



CHYTftlDIUM. 



mata ; in other words, the true-blood sys- 

 tem begins at the Echinodermata. Below 

 the Echinodermata, viz. in the Polypi and 

 Acalephee, the digestive and circulatory 

 systems are identified, consequently the ex- 

 ternal medium is admitted directly into the 

 nutrient vessels. This circumstance con- 

 stitutes a fundamental distinction between 

 the chylaqueous system and that of the true 

 blood, into which, under no conditions, is 

 the external inorganic element directly 

 introduced. 



In every class in which the chylaqueous 

 liquid exists, it is charged more or less abun- 

 dantly with organized corpuscles. These 

 corpuscles are marked by distinctive cha- 

 racters, not in different classes and genera 

 only, but in different species, entitling these 

 bodies to great consideration in the esta- 

 blishment of species. In those classes, as 

 the Echinodermata, the Entozoa, and Anne- 

 lida, in which, in the adult animal, these 

 two orders of liquids coexist, though dis- 

 tinct, in the same individual, an inverse 

 proportion prevails between them, as re- 

 spects their magnitude or development. 

 The system of the chylaqueous liquid does 

 not exist in the adult, but only in the larval 

 state of the higher members of the articu- 

 lated series, as the Myriapoda, Insecta, and 

 the Crustacea. 



BIBL. Williams, Trans, and Proc. of Ren/. 

 Soc. 1852 (the former contains figures of the 

 corpuscles); id. Ann. N. H., passim after 

 1852; Agassiz, Sieb. and Koll. Zeitschr. 

 1856, vii. 176; Nicholson, Zool. 1878. 



CHYLE. The chyle consists of a liquid 

 which coagulates when removed from the 

 vessels, containing in suspension molecules, 

 nuclei, colourless corpuscles, and coloured 

 blood-corpuscles. 



The molecules (PI. 50. fig. 2 a) are very 

 numerous, and probably consist of fatty 

 matter surrounded by a coat of a proteine- 

 compound ; to them is owing the milky ap- 

 pearance which the chyle possesses during 

 active digestion. They form the molecular 

 base of Gulliver. The free nuclei (PI. 50. 

 fig. 2 6) have a somewhat homogeneous 

 aspect; they are not numerous, about 

 1-11,000 to 1-5600" in diameter, frequently 

 appearing cell-like and granular after the 

 addition of water. They are only met with 

 at the origins of the lacteals, in the mesen- 

 tery, and in the vasa efferentia of the me- 

 senteric glands, but never in the thoracic 

 duct. The chyk-corpusdes (PI. 50. fig. 2 c), 

 which are identical with these of the lymph 



and the colourless corpuscles of the blood, 

 are pale, round, nucleated cells, 1-4500 to 

 1 2000" in diameter; their contents be- 

 come turbid when water is added; and they 

 are rendered very transparent by the addi- 

 tion of acetic acid, the granular nucleus 

 becoming at the same time very distinct. 

 Sometimes they exhibit a number of Amoe- 

 ba-like processes (PI. 50. fig. 2 d). At the 

 origins of the lacteals the chyle-corpuscles 

 are few in number, or even absent ; near the 

 mesenteric glands, they are met with under- 

 going division. The coloured blood-corpus- 

 cles are probably derived from without. 

 Chemically, the chyle consists of a saline 

 liquid, containing albumen and fibrine in 

 solution, the latter when coagulated form- 

 ing a soft and loose clot. 



BIBL. Kolliker, Mikrosk. Anat. ii. 561 ; 

 Wagner, Handwort. art. Chylus ; id. Elem. 

 ofPhys., by Willis; Gulliver, Gerber's Anat.; 

 Lister, Dublin Hosp. Gaz. 1857, 347 ; Frey, 

 Histol. $c. p. 146 ; and the Bibl. of CHE- 

 MISTRY. 



CHYLOCLA'DIA, Grev. A genus of 

 Laurenciacese (Florideous Algae), containing 

 a few British species, with fronds of small 

 size, composed of a branched, cylindrical 

 and tubular structure, cut off into chambers 

 within by diaphragms at intervals, and filled 

 with a watery juice. The walls are com- 

 posed of small polygonal cells. Nageli has 

 given the minute anatomy ofC.(Lomentaria) 

 kalifornis. The spores are wedge-shaped, 

 contained in tufts in ceramidia borne on the 

 branchlets. The tetraspores, 3-partite, are 

 immersed in the branchlets. 



BIBL. Harvey, Mar. Ala. pi. 13 B ; Phyc. 

 Brit. pi. 145, &c. ; Grev. Ala. Brit. pi. 14 ; 

 N&geli.Alfftn-wgteine, 246, pi. x. figs. 13-21. 



CHYTRID'IUM, Braun. A genus of 

 Unicellular Algae, perhaps allied to the JM y.\- 

 omycetes (Sachs), consisting of minute, glo- 

 bose or pyriforin, usually colourless cells, 

 operculate at the summit, with a root-like 

 base, attached to Confervoid or allied plants, 

 and penetrating their cell-walls. Zoospores 

 very numerous, globular, with a single very 

 long cilium. 



C. olla (PI. 5. fig. 7). 



The commonest form is that of a some- 

 what ovate cell 1-5000 to 1-2000" long, 

 sessile by the thick end on the outside of 

 the cell- wall of the plant it infests, and, 

 according to Braun and Cohn, sending fine 

 radical tubes into the interior ; the cell- 

 contents of the infested cell are usually 

 found disorganized and discoloured. In 



