66 FRESH-WATER RHIZOPODS OF NORTH AMERICA. 



terminated behind in a conspicuous villous ball, which often exhibited in 

 its interior one or several contractile vesicles. The endosarc contained 

 many crystals and but little food, though it was abundant with the ani- 

 mals. The nucleus appeared unusually small, and such likewise appeared 

 to be the case with the contractile vesicles, of which there were commonly 

 several. 



Some moist moss, from crevices of the pavement in the yard attached 

 to my house, collected in June, was placed in a dish with clear water. 

 After a few days a drop of water squeezed from the moss was found to con- 

 tain some small Amoeba?, in association with the common Wheel-animalcule 

 {Rotifer vulgaris), etc. The Amoeba?, figs. 14, 15, 16, pi. II, were usually 

 clavate in shape, though modified incessantly by broad pseudopodal lobes 

 projecting laterally, and they mostly terminated in a minutely villous ball. 

 The endosarc contained the usual constituents. They moved actively, and 

 measured about 0.06 mm. long. 



Some water with abundance of diatoms, desmids, etc., collected in 

 an extensive sphagnous swamp on Broad Mountain, Schuylkill County, 

 Pennsylvania, in September, contained many Amoeba?, such as are repre- 

 sented in figs. 1-3, pi. VIII. Commonly they exhibited a sausage-like 

 shape, or an elongated clavate form, and reached the length of 0.25 mm. 

 They glided along with little change, or they often projected one or two, 

 and occasionally more, digitate pseudopods from the sides. Frequently 

 also smaller and narrower pseudopods were projected in a divergent manner 

 at the sides of the back end of the body, which terminated in a villous 

 process of variable form. The pseudopods contiguous to the latter would 

 assume in contraction the form of cylindroid villous processes. A con- 

 spicuous nucleus and one or more contractile vesicles were constantly 

 present. 



OU11AMCEBA. 



Greek, oura, tail; amceba. 



Animal possessing the same essential characters as the genus Amoeba, 

 but in addition provided with fixed filamentous appendages habitually 

 trailing from the postei-ior extremity of the body. Filaments flexible, 

 cylindrical, tubular, inarticulate or articulate, resembling the mycelial 

 threads of fungi, perfectly passive, and neither retractile nor extensile. 



