36ti DESCRIPTION OF [Rotatoria. 



Body elongated, cylindrical, attenuated posteriorly ; fork 

 short. It has a curious internal pouch beneath the 

 eye; vibratile organ lateral, as in Pleurotrocha. Length 

 l-144th. 



618. NoTOMMATA copeus. The telegraph Notommata. 

 — Body large, attenuated at both ends ; tail small, and 

 indurated. This curious creature has a long bristle on 

 each side of its body, and on each side of the head a stout 

 branch, called, by Dr. Ehrenberg, an auricle ; these have 

 vibratile cilii around their ends, and, like the setae, stand 

 out, so that it appears like a cross : a thick gelatinous 

 substance covers the body ; the back terminates in a 

 somewhat hard point, which is a true tail, between which, 

 and the foot, the discharging opening is situated. When 

 creeping, the large vibratile arms are withdrawn, but it 

 vibrates with the frontal cilii and proboscis. Fig. 416 

 represents the creature extended. Length l-36th. 



619. Notommata centrura. The spined-tailed Notum- 

 mata. — Body large, attenuated at both ends; tail small, 

 indurated ; auricles small, and no lateral setee present ; 

 this is often enveloped in a thick slime, in which articu- 

 lated threads of Hygrocrocis vegetate, giving the animal- 

 cule a hairy appearance. It swims awkwardly. Length 

 I-36th. 



620. Notommata brachyota. The short-eared Notom- 

 mata. — Body small, slightly attenuated towards the ends ; 

 no tail, auricles very small ; it has two dark spots near the 

 eye ; foot forked. Length 1-1 20th. 



Genus CLV. Synchaeta. The bristle-headed Rota- 

 toria have a single cei*vical eye ; rotatory organs compound, 

 the clusters six to ten, and armed with from two to four 



