392 DESCRIPTION OF [Rotatoria. 



different views of this animalcule viz., back, under, and 

 side, the first and last having the rotatory organs extended 

 and in motion. Length 1-1 40th. 



681. METOPIDIA acuminata. The pointed Metopidia. 

 Lorica depressed, nearly flat, oval in shape, anterior slightly 

 excised, posterior pointed. This species resembles Colurus, 

 but, in the latter genus, the eyes are very close together, 

 and the lorica open beneath. Found amongst oscillatoria. 

 Length l-240th. 



682. METOPIDIA triptera. The three-sided Metopidia. 

 Lorica oval, triangular, back crested : a section would re- 

 semble fig. 443. Found amongst conferva. Length 1 -200th. 



Genus CLXXVI. STEPHANOPS. The diadem or coronet 

 Rotatoria have two eyes in front, the foot furcated, the 

 lorica depressed or prismatic, and the front provided with 

 a hood or diadem. The lorica, in two species, has thorn- 

 like processes posteriorly. In one species a longitudinal 

 muscle is observed on each side (anteriorly), two muscles 

 for moving the foot, and from three to five belonging to 

 the compound rotatory organ. They have an cesophagal 

 head, with single-toothed jaws, and a short oesophagus. 

 One species has a two-partite alimentary canal, the others 

 a simple one ; two species have glands; an ovarium exists 

 in all ; a contractile vesicle in two. The red eyes are 

 situated on each side, near the frontal edge in two species ; 

 in one they are yet unknown. The hood remains extended, 

 even when the creature withdraws within its shell. 



683. STEPHANOPS lamellaris (Brachionus lamellaris, M.) 

 The tri-pointed Stephanops has a lorica with three spines 

 posteriorly. The rapid movement and transparency of 

 this animalcule renders its organization difficult to observe. 



