98 Mr. H. J.Carter on the Freshwater Sponges of Bombay. 



purpose I took small portions of the yolk-like substance from the 

 seed-like bodies of dried pieces of each of the sponges, and after 

 having placed them in separate watch-glasses with distilled water, 

 set them aside for a few days until the protean s made their ap- 

 pearance*. I then began to compare the latter with one another 

 in the different watch-glasses, but instead of finding that each 

 species of Spongilla had its peculiar form, I frequently found 

 that the kind of protean I had determined on as proper to one 

 species, was to be seen on the same or on the following day in a 

 watch-glass containing yolk-like substance from the seed-like 

 bodies of another species, and so on throughout all the glasses. 

 It therefore would appear, that in whatever the specific distinctions 

 of the diff'erent proteans consist, too much stress must not be laid 

 upon their external forms. 



Respecting the position which Spongilla holds among orga- 

 nized bodies, I feel incompetent to offer an opinion. All who know 

 anything about the subject are aware that it is closely allied to 

 both the animal and vegetable kingdoms, but it is for those who 

 are best acquainted with that part of the chain which unites 

 these two great conventional divisions, to assign to it its proper 

 link. 



I might here state, however, that we are indebted to Dujardin 

 for the earliest notice of the resemblance of the sponge-cell to 

 the Proteus -f. Ehrenberg^s name for the Proteus is Amoeba ; he 

 has also applied the same name to the fifth family of his naked 

 Phytozoaria polygastrica, Sect. 3, Pseudopodia, in which is in- 

 cluded the genus Amoeba. 



Finally, I stated in the P.S. to my " Notes J," that the Pro- 

 teus fed on its like after the manner of the Hydra. The fact 

 which induced me to make this assertion has been already 

 mentioned, but the subject requires further investigation be- 

 fore it can be considered conclusive. It is difficult to conceive 

 why the Proteus should enclose within its cell-wall one of its own 

 like, if it were not for the purpose of feeding upon it ; added to 

 which the constant accumulation of refuse matter, which, issuing 

 from the faecal orifices, settles on the surface of the living sponge, 

 when kept in a horizontal position, shows that there is a con- 

 tinual elimination going on of material which is no longer useful 

 in its oeconomy, and in connection with the fact to which I have 

 alluded, would seem to point out the probability that such ejecta, 

 to a certain extent, consist of the cast-off parts of organisms from 

 which the nutrient parts have been abstracted. 



* Throughout all my experiments distilled water was used, and e\''ery 

 precaution taken to preclude as far as practicable the introduction of foreign 

 matter. 



t Ann. des Sc. Nat. n. s. x. p. 5. + Ann. and Mag. Nat. Hist. loc. cit. 



