1897J MICROSCOPICAL JOURNAL. 115 



a point ; posterior evenly rounded ; oval aperture incon- 

 spicuous but very capacious, situated in the truncation ; 

 flagella originating together at the apex; the anterior 

 one equalling one-half the body length and the posterior 

 one twice the body length, and much heavier ; contrac- 

 tile vesicle large, very conspicuous and located well up 

 in the anterior body half; nucleus round and in posterior 

 body half; endoplasm intrinsically clear and of a blueish 

 tint, but generally filled with large food" grains; locomo- 

 tion exceedingly rapid and by revolution on long axis. 

 Size from 1-2500 to 1-1100 inch. Habitat— Putrid vege- 

 table macerations. Transverse fission. 



The movements of this infusorian are so rapid that a 

 view of the flagella is made very difficult; especially is 

 this so in respect to the anterior shorter one. At times 

 the posterior longer flagellum is twined about the body. 

 The oval aperture would never be suspected to exist if 

 the infusorian was found feeding on bacteria ; it is only 

 when seen engulphing or attempting to engulph largie 

 particles of food that the position and capaciousness of 

 the oval aperture can be demonstrated. The writer had 

 under observation a specimen that made quite a number 

 of attempts to swallow food more than thrice its own di- 

 mensions. Where it is found with abundance of food 

 the nucleus and contractile vesicle are obscured by the 

 large globular food grains it contains. It is a veritable 

 scavenger. A dead Pluronema has been seen surrounded 

 by dozens of them intent on devouring the remains as 

 rapidly as possible. 



Family. — AnisonemidsB. S. K. 



Grenus. — Diplomastix. S. K. 



Species.- — Diplomastix agilis (figs. 8 and 9). 

 Body sub-obovate, compressed; less than twice as long as 

 wide ; dextral border of greater convexity than sinistral ; 

 anterior slightly truncate transversely ; dorsum convex 



