STUOr OF PELOilYX.V PALCSTIUS. 393 



individuals, or parts of individuals, takes place at all iu nature, 

 it would appear that Pelomyxa should rather be regarded as a 

 Plasmodium. The single nucleus observed in the amoebae and 

 the multinucleate condition of Pelomyxa are facts consistent 

 with such a theory. 



SiiMMAur AND Conclusions. 



The conclusions arrived at in this investigation may, then, bo 

 briefly summarized as follows : — 



(1) The rods are symbiotic bacteria, which complete their 

 development within the protoplasm of Pelomyxa and are then 

 ejected, breaking down into free " swarmers," which are ingested 

 by other Pelomyxce, and recommence the c^'cle. 



(2) The refringent bodies are proteid iu nature ; they consist 

 of some form of albumin, which is probably a waste product of 

 the metabolism of Pelomyxa ; they have a twofold relation to 

 the bacteria, supplying them with a point of attachment neces- 

 sarj'- for their development, and (probably) also with a source of 

 nourishment. 



(3) The pseudopodia of Pelomyxa are not always blunt and 

 lobose, but often exceedingly attenuated and acute, are often 

 reticulate, or anastomosing, and of a different character from 

 any hitherto described for this animal. Classifications based on 

 the lobose nature of the pseudopodia are hereby invalidated. 



(4) The division of Pelomyxa is of a simple character, in which 

 the nuclei do not play an important part. The only other form 

 of reproduction observed has been, in a single instance, the 

 production of amoebse, whereby the observations of Greeff and 

 KorotnefE are partly, and those of Penard entirely confirmed. 



(5) Tinder certain circumstances a portion of one Pelomyxa 

 may fuse w ith the protoplasm of a portion of a second Pelomyxa, 

 the inference from this observation being that it may prove 

 necessary to regard Pelomyxa as a plasmodium. 



BlBLIOGRAPUy. 



(1) Gkkefk, E. — Archiv fiir mikrosko,nsche Anatomic, Bd. x. 



1879, p. 51. 



(2) Lkidt, J. — Presh-water K'lizopods of N. America, 1879. 



(3) KoEOTNEFF, A. A. — Archives de Zoologie Exp., vol. viii. 



1S79-80, p. 167. 



