378 DESCRIPTION OF [Rotatoi-ia. 



toothed) jaws, a very short oesophagus, and a simple conical 

 alimentary canal, with two roundish glands. Both ova- 

 rium and two sexual glands, with a contractile vesicle, are 

 found. Transverse circular vessels, and six pair of tre- 

 mulous organs, attached to the seminal glands, constitute 

 the vascular system. A purse-shaped dark (colourless) 

 body in the neck, connected by a narrow^ process to a 

 large frontal ganglion, containing from six to twelve red 

 points, of which the anterior one is most marked, indicate 

 a sensitive system. 



648. Cycloglena lupus {Cercaria lupus, M.) The 

 water-wolf Cycloglena. — Body ovato-oblong, or conical, 

 not auricled ; foot terminal, and short. Plate x.,Jig. 425*, 

 represents a back view, and fig. 426 a side view. Length 

 l-120th. 



649. Cycloglena (?) elegans. The elegant Cycloglena. 

 — Body ovate, not auricled ; foot inferior j toes long. 

 Length 1-1 90th. 



Genus CLXVL Theorus. The many-eyed Hydatinaea 

 have numerous eyes (more than three), disposed in two 

 groups at the neck; the foot is furcated. A compound 

 rotatory organ, together with two muscles of the foot, an 

 oesophagal head, with two one-toothed jaws, a short oeso- 

 phagus, a simple conical alimentary canal, with two glands, 

 a ball-like ovarium, with two male sexual glands, and a 

 double group of colourless cervical eyes, are the details of 

 organization at present known. The frontal uncinus, or 

 hook, is perhaps a respiratory tube. 



650. Theorus vernalis. The spring Theorus. — Toes 

 small ; no frontal uncinus. The movement of this crea- 

 ture is active and vehement, like that of an animal of 



