188 DESCRIPTION OF [Poh/gasfriccf. 



boscis belongs to nine species out of the eleven, and a double appear- 

 ance of this organ has been observed in the E. sanguinea, ascribable, 

 no doubt, to the preparatoiy condition of the animalcule for self- 

 division. 



In Euglena hyalina, E. plcuronedes, and E. longicauda, nutritive 

 cells are generally visible, but in the other species they are obscured 

 by the masses of green ova, which colour their bodies. Certain in- 

 ternal appearances have been recognized, which Ehrenberg supposes 

 to be of a male generative nature. Longitudinal self-division has 

 been observed in E. acus, and the preparation for it in E. sanguinea, 

 as before mentioned. 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 E. amhlyophis. 



The genus Euglena of Ehrenberg, says Dujardin, contains some 

 species of a compressed leaf-like form, and quite deficient of con- 

 tractility, and ought to be placed in the genus Phams of the family 

 Thecamonadina. 



Respecting the so-called red eye, the French naturalist also remarks 

 that it is far fi'om being a tme eye, appearing as it does often like an 

 irregular collection of two, thi'ee, or even four granules, sometimes 

 with considerable intervals between them, but tliis appearance I have 

 observed in several JEntoinostracea when the magnifying power of the 

 microscope is not sufficient. 



The Euglena are undoubtedly animals, yet their composition is 

 binary, and they evolve oxygen, two characteristics of plants. But 

 on the other side, certain mushrooms and other cryplogamous plants, 

 are tertiary in composition, having that usual animal element, 

 nitrogen ; and they evolve carbonic acid, both characters of animals. 



In the 'Miniature Achromatic Microscope' with a magnifying 

 power of 150 diameters, most of the species may be well observed. 



E. sanguinea {Cercaria viridis, M.) Body extensible, of an oblong 

 cylindrical or spindle-shaped form, with the head gi'eatly rounded ; 

 the tail is short, conical, and somewhat pointed. Proboscis longer 

 than the body in its extended condition. "When young, they are 

 green, but when full grown, are of a blood red colour. The motion 

 of this multifonn animalcule is generally slow, and it sometimes 

 revolves upon its longitudinal axis in swimming. Its coloiu' is not 



