Hydatinaea.'] THE INFUSORIA. 379 



prey. Fig. 427 represents a back view of this animalcule 

 extended, with six colourless eyes in each group ; Jig. 428 

 is another specimen with four eyes ; and^g. 429 an animal- 

 cule with body contracted, but jaws extended. Found 

 amongst oscillatoria. Length 1-1 40th. 



651. Theorus uncinatus. The hook-lipped Theorus. — 

 Toes long, a frontal uncinus or hook present. Six visual 

 points have been seen by Ehrenberg. Found amongst 

 oscillatoria. Length l-240th. 



