OF THE CRYPTOMONADII^A. 



513 



The name is indicative of the elongated apex. These Infusoria being but 

 imperfectly known, one species only is described : — 



OxYEEHis marina (xxvi, 9 a, b.) — Colourless j subcylindrical rugose, rounded 

 posteriorly. 1-520". In the Mediten*anean. 



The next thi-ee genera are taken from Perty, the first being one of his 

 Cryptomonadina, the others Thecamonadina : — 



Genus PHACOTUS (XIX. 7, a, b, c).— Body round, biconvex, ^dth two 

 (possibly four) filaments. 



Phacotus viridis. — Green, usually 

 divided through the middle by a clear or 

 a dark line. Margin acute ; the central 

 part more or less convex, sometimes 

 elevated into a sharp angular ridge, ren- 

 dering the fig-ure fom"-sided. The shell 

 shows a double contoui', and persists 

 some days after the death of the indi- 



vidual. Medium size 1-1440". Among 

 Confervas. Bern. It = Cn/pfo?nonas 

 lenticidaris (E.). Like Dujardin, Perty 

 removes Clicetotijphla and ChcBtoglena 

 from the Peridinisea to the Thecamo- 

 nadina. The foimer genus he retains, 

 but merges the latter in his group 

 CJionemonas. 



Genus TRYPEMOXAS = generaUy TEACHELOMOXAS (Ehr.) (XIX. 9, 

 10, 11). — Shell globular or elliptic, with a small round apertui'e (the elevated 

 margin of which frequently produces a funnel-Like appearance), from which 

 the filament protrudes ; colour green, with a red stigma ; lorica at first hyaline, 

 then purj)lish, and lastly brown, thick and opake ; not armed, but apparently 

 porous from the presence of numerous pimcta indicating the absence of 

 deposit, as elsewhere. Perty justly objects to the term Trachelomonas, as 

 prone to cause confusion of ideas from its etymology signifying beings with 

 necks, which none of those it includes possess. 



Trypemoxas volvocina (xix. 9, 10) = Trachelomonas volvocma ; and T. cylindrica 

 (xix. 11) = Trachelomonas cylindrica and T. nigricans (Ehr.). 



Genus CHOXEMOXAS (XYIII. 35 a, b, c, cZ).— Green with a red stigma ; 

 testa hard, ellipsoidal, with a funnel-shaped opening at the anterior end — from 

 which tivo filaments proceed. It represents in part the genera CJicetogUna, 

 Pantotrichum, and Lagenella (E.). 



in pools of snow-water, and beneath the 

 ice. Two varieties occm* : — a. glabra, 

 with a smooth lorica, which is no other 

 than the Lagenella euchlora (E.) ; 6. 

 imijilis, Tsdth a single filament, equiva- 

 lent to ChcBtoglena volvocina (E.). The 

 very hispid examples of this Chonemonas 

 are = Pantotrichum Lagenula, placed by 

 Ehrenberg among his Cyclidina. 



C. acuminata. — Shell oval, strongly 

 pointed posteriorly ; bristles scarcely ob- 

 servable. Fimnel at front distinct. 

 1-500". Hyaline and quite smooth speci- 

 mens also occurred. On the St. Gothard. 



Chonemonas Schrankii (x\tji. 35 a, 

 b, c, d), formerly named C. hispida. — 

 Lorica clear or dark bro\\Ti, more or less 

 spinous. Filaments double the length, 

 and hyaline. Portions of the lorica ex- 

 hibit apparent pores, and empty speci- 

 mens often decussating lines. The gi'een 

 contents escape imhuii; on fi'actming 

 then' enclosing case, which they gene- 

 rally do not fill. When fission proceeds, 

 the contents alter their form, and the 

 filaments disappear. Onward movement 

 not rapid, seldom oscillating, but actively 

 revolving. 1-900" to 1-540". At Bern, 



Genus DREPAXOMOXAS (Fresenius). 



Drepanomonas <7ewtote. — Colomiess; 

 falcifoi-m, compressed; pointed at each 

 end, \s-ith five outspreading furrows, of 

 which two are on either flat side, and 

 one on the convex edge. In the centre 

 of the concave smface is a ventricose 

 swelling with a small tooth-like process ; 

 a similar process is remarked beneath 



the apex. From near the last, several 

 lines extend upwards and outwards. In 

 one aspect an undulating line is percep- 

 tible along the convex margin; this is 

 also \TLsible in the loricae of dead speci- 

 mens. Internally are only colom-less 

 granules, imparting a pearly hue. On 

 one occasion a vacuole was seen ha^ino- 

 2l 



