Fuchlanidota.] THE INFUSORIA. 389 



two long spines at the base of the foot; toes three : it has 

 a slight dorsal ridge. Figs. 454, 455, represent this crea- 

 ture in different positions; andjg. 456 the oesophagal head. 

 Found amongst Ceratophyllum, &c. Length l-120th. 



672. DINOCHARIS tetractis. The four-pointed Dino- 

 charis. Lorica acute, triangular; horns two, at the base of 

 the foot ; toes two. This specit?s has longer toes than the 

 others, and the body is comparatively shorter. Found in 

 lemna and Ceratophyllum. Length 1-1 20th. 



673. DJNOCHARIS paupera. The simple Dinocharis. 

 Lorica acute, triangular ; horns two, at the base of the foot, 

 scarcely perceptible, toes two, short. Length 1-1 20th. 



Genus CLXXIII. MONURA. The styliform-footed Ro- 

 tatoria have two frontal eyes, and a simple styliform foot. 

 The lorica is somewhat compressed and open upon the ven- 

 tral surface : anteriorly is a hook-like process, which can be 

 withdrawn. In one species the vibratile organ has four 

 to six muscular bulbs ; in both an oesophagal head, with 

 two jaws toothed, a very short oesophagus, and a simple 

 alimentary canal, with two spherical glands, are observed ; 

 also, an ovarium, with single large ova, and in one species 

 the vesicle of the germ has been observed. The eyes are 

 red, moveable, and seated upon nervous masses. The 

 species are not only difficult to distinguish from each other, 

 but also from the genus Colurus; the toes of the latter ap- 

 pearing single until pressure is used. 



674. MONURA coluris. The obtuse Monura. Lorica 

 oval, obtuse, obliquely truncated posteriorly, eyes near to 

 each other. Length of lorica 1 -280th. Siberian specimens, 

 1 -400th. 



675, MONITRA ditlcis, The pointed Monura. Lorica 



