GENUS DIPLOPHRYS— DIPLOPIIRYS AECHERI. 257 



Diplophrys archeri, in its mature individual condition, is described 

 by Professor Schulze * as a minute globular body, 0.01 mm. to 0.02 mm., 

 from opposite poles of which there radiates a tuft of fine and mostly 

 unbranching pseudopods. The transparent, faintly granular protoplasm 

 composing the body contains a bright refractive corpuscle of variable size, 

 usually of an amber color, less frequently paler or even colorless, and some- 

 times light ruby red. 



I have not observed Diplophrys in the isolated and mature condition; 

 it having perhaps escaped my attention from its very diminutive size. On 

 several occasions I have seen what I have supposed to be the young con- 

 dition, in which numerous individuals were associated in a coherent mass, 

 resembling similar groups described and figured by Professor Greeff and 

 Mr. Archer. 



Professor Greeff f has suggested the probability of such a group, 

 represented in his fig. 29, pi. xxvii, and other forms, figs 25-28 of the 

 same plate, more characteristic of Diplophrys archeri, having a genetic 

 relation with Acanthocystis spinifera. A similar group Mr. Archer referred 

 to another animal, distinct from Diplophrys, with the name of Cystophrys 

 oculea.% 



Subsequently Professor Greeff § recognized the forms represented in 

 his figs. 25-28, above indicated, as belonging to Diplophrys archeri, and 

 further became convinced that the group represented in his fig. 29, pre- 

 viously described by him without name, together with the Cystophrys 

 oculea of Archer, were colonies of Diplophrys archeri, probably resulting 

 from segmentation 



The rhizopodal groups which I have observed, and regarded as per- 

 taining to Diplophrys archeri, were obtained in sphagnous bog-water, on 

 Broad Mountain, Schuylkill County, Pennsylvania, September, 1876, and 

 at Atco, New Jersey, October, 1877. 



The groups were composed of multitudes of minute globular indi- 

 viduals aggregated in masses, which in their movements slowly underwent 

 change of shape. A group closely aggregated and nearly spherical 

 measured about 0.04 mm. Gently gliding across the field of view, it 



* Arckiv f. mikros. Anatomic, xi, 1875, 127. 



t Ibidem, v, 1869. 



{ Quart. Jour. Micros. Science, ix, 1860, pi. xvii, fig. 3. 



J Areliiv f. mikros. Anatomic, xi, 1875, 15. 



17 RHIZ 



