terior end of the body (B.bursaria).The anterior end of the body is cut 

 obliquely in the direction of the ventral surface and more or less strong- 

 ly bent toward it. The dorsal surface is more convex than the ventral. On tb 

 ventral side in the anterior part of the body is placed a small paristome, 

 having the appearance of a not specially deep pit, somewhat covered at the 

 anterior part by the bent anterior end of the body. The left margin of the 

 oeristome is provided with a scallop, whi le the right forms a straight line 



The whole body .vith the exception of the peristome,is covered with cii- 

 arranged on small protuberances or papillae. 5hey are arranged in long* 

 tudinal rows and cause in B.minutus and busaria a longitudinal striping of 

 the body. The ciliary stripes extend meridionally from the posterior to 

 the anterior end of the bodyjon the ventral side the median stripes stopat 

 the lower (posterior) and often at the left margin of the peristome,whi le 

 the lateral ones encircle the peristome and unite in bow-shape in the ant 

 ior part of the body where it bends to the ventral side. In B.elongatus 

 longitudinal stripes are aot visible. The ciliary covering is very variable 

 in different species: in B.bursaria the body is evenly covered with short, 

 fine and thicKly set cilia;in B.minutus the cilia are long, bristle-like 

 and at the anterior end of the body are much thicker than at the posterior 

 while the anterior ones are usually curved to the ventral surf acejf inally 

 in B.elongatus the cilia are also long, bristle-like, but are very far apart 

 *nd only at the anterior end of the body cover it a little more closely. 



The entoplasm consists of a thin, transparent and homogeneous layer, or 

 If an alveolar layer and a very thin pellicle (B. busaria). The entoplasm 

 Ls fine grained and contains many highly refractive particles. 



The mouth opening is small and lies in the hollow of the peristome at 

 the posterior end, somewhat near its left side. There is no oesophagus or it 

 is in appearance small and extremely short, cylindrical tubular (B.bur- 

 saria) .Almost all the peristome is covered with a bag-like undulating mem- 



* 



pane, attached along the left, posterior (lower) and right margin of the 

 peristome (B.minutus) , or extending only to the middle of the left (B.bur- 



