TREMELLA. 



[ 649 ] 



TRICHIA. 



ments uncovered ; legs four pairs, with long 

 plumose hairs, fourth pair slender, and two- 

 branched; antennae small, flat, and two- 

 jointed; second pair of foot-jaws two-jointed, 

 and not in the form of a sucking disk. 



T. caudatus. Found upon the body of the 

 skate. Male much smaller than the female. 



BIBL. Baird, Brit. Entomostraca, 280 ; 

 Thompson, Ann. Nat. Hist. 1847. xx. 248. 



TREMELLA. See TREMELLINI. 



TREMELLINL A family of Hymeno- 

 mycetous Fungi, consisting of polymorphous, 

 often convoluted or lobed, more or less ge- 

 latinous masses, growing upon branches or 

 stumps of trees, in crevices of the bark, or 

 on the dead v r ood. The hymenium extends 

 over the whole of the upper exposed surface, 

 and, from the recent researches of Tulasne, 

 appears to present remarkable characters. 

 The gelatinous substance of these Fungi is 

 composed of ramified filaments, with more 

 or less effused mucilage between them. In 

 Tremella a portion of the filaments termi- 

 nate at the surface at first in expanded glo- 

 bular cells, which become divided by vertical 

 septa into four somewhat pyriform cells 

 (basidid)-, from each of these arises a slender 

 filament (sterigma), which terminates in a 

 slender point tipped with a globular spore 

 (stylospore or basidiospore). Other filaments 

 coming to the surface in like manner ramify 

 extensively, with short divergent branches, 

 finally bearing numerous minute globular 

 bodies (spermatia), solitary or in groups of 

 four, which, like the basidiospores, fall off 

 and rest on the hymenial surface, involved 

 in jelly, but, unlike those, do not germinate. 

 The basidiospores are about 1-3000" in dia- 

 meter, the spermatia about 1-12000". In 

 Tremella mesenterica the surface coveredwith 

 basidiospores assumes a whitish colour ; the 

 layers of spermatia and the jelly are orange. 

 In Exidia the production of the basidio- 

 spores is similar, but the spores are reniform 

 and unilocular, about 1-2500" long and 

 1-5000" in diameter. Spermatia have not 

 been detected. 



In Dacrymyces the basidia are represented 

 by simple clavate or bifurcated branches at 

 the hymenial surface, these terminating in 

 points bearing single reniform spores exhi- 

 biting three septa (quadrilocular). In ger- 

 mination some of these spores produce a long 

 filament from each loculus; others behave 

 differently, producing the spermatia of the 

 plant, each loculus sending out a short 

 pointed process bearing a globular cellule 

 exactly resembling the spermatia of Tremella. 



Other examples of Dacrymyces bear a dif- 

 ferent kind of reproductive body, apparently 

 representing conidia. In these the peri- 

 pheral filaments terminate in a mass of 

 many-jointed Torula-like processes, which 

 ultimately break up into the separate joints. 

 (See DACRYMYCES and EXIDIA.) 



BIBL. Berk. Brit. Flor. ii. pt. 2. p. 215, 

 Ann. Nat. Hist. 2nd ser. xiii. p. 406. pi. 15. 

 fig. 4 ; Tulasne, Ann. des Sc. nat. 3 ser. xix. 

 p. 193. pis. 10-12. 



TREPOMONAS, Duj. A genus of Infu- 

 soria, of the family Monadina. 



Char. Body compressed, thicker, and 

 rounded behind, twisted in front into two 

 narrowed lobes, which are inflexed laterally, 

 and each terminated by a nagelliform fila- 

 ment, which produces a very lively rotatory 

 and jerking motion. 



T. agilis (PL 25. fig. 6). Body granular, 

 unequal. Length 1-1160". Found in de- 

 composing marsh-water. 



BIBL. Dujardin, In/us. 294. .'IOA>I 



TRIARTHRA, Ehr.-A genus of Rota- 

 toria, of the family Hydatinsea. 



Char. Eyes two, frontal ; foot simply sty- 

 liform ; body with lateral cirrhi or fins. 



Movement jerking. Jaws two ; each bi- 

 dentate. 



T. longiseta (PI. 35. fig. 30). Eyes distant, 

 cirrhi and foot nearly three times as long as 

 the body. Aquatic; length 1-216". 



T. mystacina. Eyes approximate ; cirrhi 

 and foot scarcely twice as long as the body. 



T. breviseta (Gosse). Cirrhi much shorter 

 than the body. 



BIBL. Ehrenberg, Infus. 446; Gosse, 

 Ann. Nat. Hist. 1851. viii. 200. 



TRICERATIUM, Ehr. A genus of Dia- 

 tomaceae. 



Char. Frustules free; valves triangular, 

 areolar, each angle mostly with a minute 

 tooth or short horn. 



Kiitzing describes fourteen species ; Smith 

 admits three British. 



T.favus (PL 13. fig. 29). Valves plane or 

 convex, angles obtuse, with horn-like pro- 

 cesses ; areolae hexagonal. Marine ; diame- 

 ter 1-240". 



T. alternans. Angles of valves slightly 

 elevated ; areola3 circular. Marine. 



T. striolatum (?). Angles subacute ; areo- 

 lation faint. Brackish water. 



BIBL. Ehrenberg, Ber. d. Berl. Akad. 

 1840; Smith, Brit. Diatomacete, i. 26; 

 Kiitzing, Bacill. 138, and Sp.Alg. 139. 



TRICHIA, Hall. A genus of Myxogas- 

 tres (Gasteromycetous Fungi) growing upon 



