188 FRESH-WATER RHIZOPODS OF NORTH AMERICA. 



out a favorable light. It is usually widest in the direction of movement of 

 the animal, and often is seen only on the side of movement. It is inces- 

 santly changing, seems defined by a more or less irregularly dentated 

 edge, and gives the impression of being a thin pseudopodal expansion 

 of the sarcode. The true pseudopods, projecting from beneath the edge 

 of the disk, are so little differentiated as to appear like pointed processes of 

 the disk itself. 



Cochliopodium seems to be a hungry animal, and is not unfrequently 

 observed in the attempt to swallow diatoms or other algas too large for its 

 capacity, as represented in figs. 18, 19. The discharge of matters from the 

 body occurs as in other rhizopods. In one instance, as represented in fig. 

 4, I observed a mass of matter discharged, looking like a portion of the 

 sarcode itself, in which was contained a diatom. 



COCHLIOPODIUM VESTITUM. 



Plate XXXII. figs. 28-28. 



Amphizonella vestita. Archer: Quart. Jour. Mio. Sc. 1871, xi, 112, 135, pi. vi.figs. 1-6. 

 Cochliopodium pilosum. Hertwig and Lesser : Arch. mik. Anat. x, 1874, Suppl. 78. 



Cochliopodium vestittim. Archer: Quart. Jour. Mic. Sc. 1877, 334. In part, including only the hirsute 

 form, mostly with interior chlorophyl-like granules. 



Body constructed as in the preceding species, but more or less covered 

 with minute rigid cils or fine hair-like appendages. Sarcode containing 

 variable proportions of chlorophyl granules, which, however, may be absent. 



Size. — From 0.04 mm. to 0.0G mm. in diameter. 



Locality. — Absecom mill-pond, New Jersey; China Lake, Uinta Mount- 

 ains, Wyoming Territory. Ireland, Mr. Archer. 



Cochliopodium vestittim (figs. 26-28, pi. XXXII), discovered by 

 Mr. Archer, was at first attributed to the genus Ampldzonella of Professor 

 Greeff; but subsequently, recognizing its difference, he accepted the posi- 

 tion given to it in the former genus by Hertwig and Lesser. These authori- 

 ties, without evident reason, substituted for it the name of Cochliopodium 

 pilosum. Mr. Archer regards both this and the more common form described 

 in the preceding article as varieties of the same species, and includes both 

 under the name of Cochliopodium vestittim. While admitting that this view 

 may be correct, and certainly it is so in the light that the so-called species 

 of rhizopods merge into one another, yet, according to the plan adopted, I 

 think it desirable to consider the two forms as distinct, 



