COLEPS. 



L 155 1 



COLLOID MATTER. 



or dentate in front; posteriorly terminated 

 by from two to five points or teeth; aquatic. 



Ehrenberg states that the oral and anal 

 orifices exist at the opposite ends of the 

 body. The gastric sacculi are readily filled 

 with colouring matter. Motion that of revo- 

 lution upon the longitudinal axis. 



A single genus : Coleps, 



COLEPS, Ehr. — A genus of Infusoria, of 

 the family Colepina. 



Char. Those of the family. 



These animals are very voracious, and feed 

 freely upon the portionsof the body of crushed 

 Entomostraca, which attract them as much 

 as sugar attracts flies. 



C. hirtus (PI. 23. fig. 33 a, Ehr.; fig. 33 h, 

 Duj.). Oval, white, carapace tabulate, 

 furrows transverse and longitudinal ; poste- 

 rior teeth three (two, Duj.); length 1-5/0 

 to 1-430". 



/3 elongatus. Cylindi'ical, elongate, length 

 as in the last. 



C. viridis. Ovate, furrows transverse and 

 longitudinal, green, posterior teeth three; 



Tn" 



length 1-960 to 1-5/0 



C. a7nphacanthus. Ovate, carapace divided 

 by transverse furrows only, anterior teeth 

 unequal; posterior teeth three, large; length 

 1-280". 



C. incurvus. Oblong, nearly cylindrical, 

 slightly curved, white, posterior teeth five ; 

 length 1-430". 



BiBL. Ehr. Infus. 317; Duj. Infus. 365. 



COLLEMA, Ach.— A genus of Colle- 

 maceae (Gymnocarpous Lichens), contain- 

 ing a number of indigenous species, remark- 

 able for the peculiar gelatinous character of 

 the frond and the beaded arrangement of 

 the gonidia, mostly growing on the ground 

 or among Mosses in damp places. Tulasne 

 has shown that they produce spermagonia, 

 with spermatia, which are generally imbedded 

 in the substance of the frond, opening by a 

 terminal pore (PI. 29. fig. 13). The fronds 

 are mostly dark olive or blackish-green. 



BiBL. Hook. Brit. Flora, v. p. 1. 211. 

 See also under Collemace^. 



COLLEMACEiE.— A family of Gymno- 

 carpous Lichens, known by the gelatinous 

 character of the (fresh) thallus, which is com- 

 posed of two kinds of filaments (see Li- 

 CHENEs), some branched and cylindrical, 

 others (gonidial) moniliform (PI. 26. fig. 13), 

 the former gradually combined into the ex- 

 cipula supporting the thecse and paraphyses, 

 constituting the apothecia. The spermagonia 

 are formed in asimdar manner. Some authors 

 have imagined that the Nostochacea? are 



early conditions of Collema, but this assump- 

 tion does not seem to be w arranted. British 

 genus : 



Collema. Thallus of uniform texture, 

 gelatinous when fresh, when dry generally 

 becoming hard and cartilaginous, polymor- 

 phous, granulated, foliaceous, lobed, lacini- 

 ated or branched. Apothecia circular, sessile, 

 rarely slightly elevated, bordered, formed of 

 the substance of the thallus, the disk some- 

 times coloured. 



BiBL. Tulasne, Mem. sur les Lichejis, Ann. 

 des Sc. nat. 3 ser. xvii. 29 & 202. pi. 6 & 7 ; 

 Fries, Summa Veget. 175; Itzigsohn, Botan. 

 Zeit. xii. p. 521. 1854. 



COLLENCHYMA.— A pecuhar kind of 

 thickening of cellular tissue in the subepi- 

 dermal layers of many herbaceous stems, 

 such as RumeXy Beta, Chenopodium, &c., 

 which some have regarded as intercellular 

 substance, while others, more correctly, have 

 stated it to consist of metamorphosed second- 

 ary layers inside the cells. See for the dis- 

 cussion. Intercellular Substance. 



COLLETONEMA, Bre^isson.— A genus 

 of Diatomacese. 



Char. Frustules navicular, connate, ar- 

 ranged in rows, and immersed in a gelatinous 

 amorphous mucus, forming a filiform frond. 

 Aquatic. 



C. viridulum,. Frustules crowded and spi- 

 rally arranged ; front view^ linear-oblong, 

 truncate, slightly and gradually attenuate 

 towards the ends; valves lanceolate, obtusish, 

 not striated (?) ; length of frustules 1-610''; 

 breadth of frond 1-670 to 1-450". 



Doubtful species : 



C. (?) amphioocys {Naunema amp., E.). 

 Mexico. 



C. (?) americanum {Naun. amer., E.). 

 Hudson's River. 



BiBL. Kiitzing, Sp. Alg. 105. 



COLLOID MATTER, exudation and 

 CORPUSCLES (animal). 



The term colloid matter or exudation is 

 applied to a transparent, viscid, yellowish, 

 structureless or slightly granular matter, 

 resembling liquid gelatine. In a state of 

 greater consistence, it sometimes forms flakes 

 or irregular masses, w hich occasionally pos- 

 sess a laminated structure. 



In a third form it constitutes spherical, 

 rounded or oval, sometiras flattened micro- 

 scopic corpuscles — simple masses of sarcode 

 (PL 30. fig. 22 a). These are either homoge- 

 neous, or exhibit numerous laminae (concen- 

 tric colloid corpuscles) (PI. 30. fig. 22 b) ; 

 sometimes a kind of nuclear body is present 



