Astasiaea.] THE INFUSORIA. 155 



Body large, elongated, cylindrical, distended or compressed, 

 and abruptly rounded at the posterior extremity ; green ; 

 head colourless ; eye large, bright red. The motion of this 

 creature is dull and serpentine, and by its evolutions might 

 easily be mistaken for the Euglena spirogyra, were that 

 creature, like this, tail- less. Group 70 represents three 

 specimens, one full grown, and the others young. Found 

 among Euglena, chiefly in the spring. Length 1-2 10th to 

 1-1 40th. 



Genus XXXIV. Euglena. The eye Animalcule. — This 

 beautiful genus of the family Astasiaea is characterized by 

 its members being furnished with an eye, a single thread- 

 like proboscis, and tail, and by their being free, that is, not 

 attached by a pedicle. The locomotive proboscis belongs 

 to nine species out of the eleven, and a double appearance 

 of this organ has been observed in the Euglena sanguinea, 

 ascribable, no doubt, to the preparatory condition of the 

 animalcule for self- division. 



In E. hyalina, pleuronectes, and longicauda, nutritive 

 cells are generally visible, but in the other species they 

 are obscured by the masses of green ova, which give this 

 colouring to their bodies. Certain internal appearances 

 have been recognized, Avhich Ehrenberg supposes to be of 

 a generative nature, and to belong to the male kind. 

 Longitudinal self-division has been observed in E. acus, 

 and the preparation for it in E. sanguinea, as before men- 

 tioned. The red visual point indicates the existence of the 

 sensitive system in this genus, and a nervous ganglion is 

 visible in E. longicauda, as in amblyophis. 



126. Euglena sanguinea (Cercaria viridis, M.) The 

 blood-red Euglena, — Body extensible, of an oblong cylin- 



