RHIZOPODA FROM NORTH AXD SOUTH AMERICA. 209' 



Family Gromiina. 



Pamphagus mutabilis, Bailei/. 



In Amer. Jouru. Sci. & Arts, vol. xv. (1853) p. 341. 

 Leidy (6), p. 191, pi. 33. figs. 1-9. 



In a pool on the Palisades this species occurs numerously ; many were 

 seen in an active state. 



Length 45-60 [x ; breadth about half the length. 



Distrihution. — New Jersey! (6); West Point, N.Y. (Bailey); Pennsyl- 

 vania (6); Wyoming (6); Iowa [Edniondson). 



PSEUDODIFFLUGIA FASICULARIS, PencU'd (8), p. 453. 



Unusually scai-ce, being found in only one gathering, where it occurred in 

 association with P. gracilis. 



The majority of individuals had smoother tests than is usual and one empty 

 test was perfectly smooth with a sharply defined narrow collar around the 

 aperture. 



Length 26-30 /i ; diameter 18-20 /u, ; aperture 10//.. 



Distribution. — Palisades, JSI.J. 



DiAPHOROPODON MOBILE, Arclier. 



In Quart. Journ. Micros. Sci. n. s. ix. (1869) p. 394, pi. 20. fig. 6. 



In one gathering of sphagnum this species was numerous, but in no instance 

 were the pseudopodia fully displayed. The test is thick but smooth and 

 pliable ; its shape is very variable, ovoid, pyriform, or even sometimes con- 

 stricted in the middle, but it is not usually compressed ; the fine cils with 

 which it is thickly covered are colourless, and under a low power appear like 

 a hyaline investment ; they are from 8-10 jx in length and become invisible 

 in Canada balsam, oil of cloves, and glycerine ; they are insoluble in cold 

 sulphuric acid. 



Length 70-113//,; breadth 50-65/6; aperture variable; nucleus about 

 20 /t in diameter. 



Distribution. — In sphagnum from Trout Pond, Good Ground, Long Island. 



Family A M p H i s T M i N A. 



DiPLOPHRTS Archeri, Barker. 



lu Quart, Joum. Micros, Sci. n. s. riii. (1868) p. 123. 



On some water-plants a young colony of embryos of this species was seen in 

 an amoeboid state ; the individuals were 4 /m in diameter, and the colony, about 

 50 fi in length, displayed numerous pseudopodia about 30-40 /t in length. 



