THE ANNALS 



AND 



MAGAZINE OF NATURAL HISTORY. 



[SECOND SERIES.] 

 No, 20. AUGUST 1849. 



IX. — A descriptive Account of the Freshwater Sponges {genus 

 Spongilla) in the Island of Bombay, with Observations on their 

 Structure and Development. By H. J. Carter, Esq., Assist- 

 ant Surgeon, Bombay Establishment. 



[With three Plates.] 



Since my " Notes ^' on these Sponges were published* I have 

 made many more observations on them, and have extended my 

 inquiries into their structure and development, so as to be able 

 to offer a more accurate account of them than I could formerly. 

 I have also ventured to name four out of the five species I have 

 described, because they either do not appear to have hitherto 

 been met with, or if before noticed, have not had their specific 

 differences described with sufficient minuteness for their present 

 identification. The only species which I think I have recognized 

 is Spongilla friabilis (Lam.), that kind so admirably described by 

 Dr. Grant t; but even here the point on which I have founded 

 my distinctive characters, viz. the form of the spicula round the 

 seed-like bodies, has not been mentioned with that minuteness 

 which renders my recognition of it entirely satisfactory. So far 

 as actual observation ^nd the information I have derived from 

 the descriptions of others extend, all the species of Spongilla 

 which have hitherto been described appear to be so amorphous, 

 that without a knowledge of their minute structural differences, 

 they are irrecognizable. Had this fact been formerly established, 

 the same course which I have pursued for their specification 

 would in all probability have been adopted from the beginning ; 

 but with only two species, Spongilla fluviatilis and lacustris and 

 their varieties J, the genus appears to have failed from its insig- 



* Trans. Med. and Phys, Soc., Bombay, No. 8. Reprinted in Ann. and 

 Mag. Nat. Hist. No. 4, April 1848. 



t Edinb. Phil. Journal, vol. xiv. p. 270. 



X Johnston's Brit. Sponges, Synopsis, p. 250. 

 Ann. ^ Mag^. N. Hist. Ser. 2. Vol. iv. 6 



