440 EVENINGS AT THE MICROSCOPE 



yet seen, and seems to be scarce; but it is highly curious 

 and interesting in appearance. It much resembles, in out- 

 line, a fish of the genus Batistes; the muzzle being some- 

 what protruded and truncate, and the form rhomboidal; it 

 terminates in a slender pointed tail. The body is obliquely 

 fluted, which gives a very singular effect; for from the 

 transparency of the tissues the lines of the opposite side 

 can be discerned crossing those next the eye, and dividing 

 the animal into lozenge-shaped areas. The color is spark- 

 ling green, but the tail and the edges of the body are clear 

 and colorless: and there is a bright red eye. At other 

 times this Euglena takes the form of a claret- bottle, or 

 an oil-flask; the muzzle being broadly truncate, or even 

 indented. 



Its motion is rapid; a swift gliding in the direction of 

 its long axis; it turns continually on the same axis, which 

 gives a waving irregularity to its course; and has a pretty 

 effect from the continual crossing of the flutings in the 

 revolving. This specimen is about T^h of an inch in 

 length, including the tail. 



EugUna deses is much larger, being about 8 forth of an 

 inch in length, though the tail is very short. It has a 

 thick body; with a round blunt head; it tapers suddenly 

 to the tail. Its color is bright green with a red eye; but 

 the presence of an infinite number of irregular oblong 

 granules and lines, with several globular vesicles, gives 

 an opacity and a blackness to its appearance. In manner 

 it is sluggish; it never swims or glides gracefully and 

 swiftly among its playful congeners, but contents itself 

 with twining slowly among the floccose stems and filaments 

 of the water-plants, or crawls upon the surface of the live- 

 box. It does not appear to change its form, otherwise 



