126 DESCRIPTION OF \_Polygaitrica. 



gibbose, filament springing mostly from an anterior constriction. 

 Length l-2000tb. Found in infusions of gelatine. 



MoNAS varians. — Body oblong, narrower in front, very soft, and 

 variable in form. Length l-650th to l-700th. 



M. intestinalis. — Body very elongated, foiTa constantly changing, 

 or one end rounded, the other tapering, to terminate in a long fila- 

 ment, motion undulatory. Length 1 -1600th. Found in the excre- 

 ment of a newt {Triton pahni2)es). " I think this is one of the 

 species of Bodo, described by Ehrenberg as met with in the intes- 

 tines of frogs." (Duj.) 



M. fluida. — Body soft, semi-fluid, fonn variable, iiTCgularly ovoid, 

 sometimes constricted posteriorly, hollowed by large vacuoles. Size 

 l-2600th. 



M. comtricta. — Body elongated, four or five times longer than 

 broad; constricted, often much so at the centre. Length l-1300th. 



Genus TJvella. The grape Monads. — The species of this genus are 

 very well characterised by their aggregating together occasionally, 

 so as to form a grape or mulberry-like mass, and by their generally 

 possessing two (?) hair-like proboscides at the mouth. Like the 

 beings forming the genus Manas, they are deficient of the projecting 

 lips, visual organ, and tail, and have the mouth situated at the 

 anterior extremity. They progress also in the direction of the 

 longest axis of their body, and are capable of complete self-division. 

 There are six species — two green, and the remainder colourless. 



This genus belongs to the aggregate Monadina of Dujardin, and is 

 thus defined by him, " animals globular or ovoid, having a single 

 flagelliform filament, and living aggregated iu spherical masses, 

 freely moving about in the liquid." He further observes that 

 isolated individuals are not at all distinguishable from simple Monads, 

 that there is no good reason to suppose the UveUa to live alternately 

 isolated, and in masses, and hence that the absence of this circum- 

 stance cannot be employed to separate them from Polytoma, or its 

 existence to characterize the latter. 



Dujardin describes only two species, viz., U. virescens, and U. 

 ro8acea=^U. glaucoma. (Ehi'.) 



U. virescens. {Folvox ma, M.) — Body ovate, and of the colour 

 that gives rise to its specific name. Found in serrated groups 



