GENUS MONAS. 239 



Monas gibbosa, Duj. 



Body oblong or spheroidal, the surface having irregular distensions and 

 gibbosities ; flagellum long and undulating, usually springing from a 

 narrowed anterior region of the body. Length 1-2500". 



This type was encountered by Dujardin in an infusion of gelatine, in company 

 with Monas lens, and of which, as he remarks, it possibly represents an altered con- 

 dition or variety. De Fromentel refers a form to this species agreeing with it in 

 general contour, but having the cuticular surface striate and granular, and with a 

 conspicuous lateral contractile vesicle. 



Monas globulus, Duj. 



Body subglobose, compressed and pointed anteriorly, constant in form ; 

 flagellum springing from the narrower anterior end ; surface smooth or 

 faintly granulate. Length 1-1700". HAB. Salt water. 



Dujardin describes this form as differing from Monas (Hderomitd) lens in the 

 more spherical form of its body, and in the absence of the superficial tuberosities 

 which frequently distinguish that species. De Fromentel reports the same type from 

 fresh water. 



Mouas mica, Miiller. 



Body oval, inconstant in form, tapering anteriorly, transparent, coarsely 

 granulate ; movement slow and oscillating. Length 1-1200". 

 HAB. Fresh water. 



This species is recognized under the above title by Miiller, Ehrenberg, and 

 De Fromentel. 



Monas vinosa, Ehr. 



Body globular; colour wine-red; motion tremulous. Length 1-12000" 

 to 6000". HAB. Vegetable infusions. 



The Monas rnbra of De Fromentel, of equally minute dimensions, and thus 

 characterized : " Body rounded, furnished with a long and relatively thick flagellum ; 

 colour bright red ; motion slow and tremulous," is apparently identical with the 

 above form. Both are, however, probably rightly referable to the Palmellaceae or 

 Protophytes. 



Monas nodosa, Duj. 



Body irregularly oblong, tapering posteriorly ; the frontal margin trun- 

 cate ; flagellum springing from the centre of this truncate border ; surface 

 nodular. Length 1-2000". HAB. Salt water. 



De Fromentel ascribes to this species a fresh-water habitat. 



Monas viridis, Duj. 



Body spherical, one half transparent, the other green ; flagellum long 

 and slender ; living socially. Diameter 1-2000". HAB. Fresh water. 



This species is probably the motile spore of some Algal. Dujardin refers it with 

 doubt to the genus, but De Fromentel has thought fit to retain it. 



