170 Mr. H. J. Carter on Parasites of the Sjjongida. 



have yet seen has led me to a knowledge of the mode of re- 

 production and development ; nor have I ever noticed any 

 more decided difference in the size of the filaments than that 

 mentioned. The whole of this part remains for futm'e obser- 

 vation to determine ; and it appears to me that snch informa- 

 tion can only be obtained from living specimens. 



The filament resembles Vaucheria in its contents being con- 

 tinuous and not septate. Vaucheria also presents a faint 

 resemblance to it in the terminal enlargements of its filament, 

 which here are for reproductive purposes ; but there is no 

 chlorophyl in Spongiophaga communis, diXidi in no other respect 

 is it like Vaucheria. 



There is an entophytic Saprolegnious cell {? Pgfhium, 

 Pringsheim) which bores its way through the sheath of 

 Spiroggra, especially under conjugation of the latter, and, 

 entering the sporangium by tubulation, again becomes inflated 

 there, nourishing itself with the contents of the sporangium, 

 and finally producing a young brood in the inner cell or infla- 

 tion, which may escape into the sporangium itself — or in the 

 outer inflation, where the embryos may escape into the 

 water — probably in these respects being influenced by the best 

 prospect of support. Here, of course, there is no chlorophyl, 

 and there are no septa in the tubulation, while the contents, 

 until they become diff'erentiated into a new brood, appear to 

 be composed of structureless transparent plasma, presenting 

 throughout nothing but an amber colour on the application of 

 iodine. 



How far Spongiophaga communis may be allied to the 

 Saprolegniege I am not able to state ; while its habits so far 

 resemble those of Thamnoclonium fiabcUiforme as to produce 

 in some Hircinice, as before stated, a pseudomorph of the 

 sponge, in which hardly any thing more remains than the 

 foreign objects Avhich formed the core or axis of the horny 

 fibre. 



Saprolegnious Mycelium. 



In 1845 (' Annals,' vol. xvi. p. 405, pi. xiii. figs. 1-6) 

 Dr. Bowerbank described a new genus of sponges under the 

 name of *' Auliskia,^^ which was characterized by the presence 

 of "minute cajcoid canals radiating from the fibre in every 

 direction." These, however, Schmidt, in his critique on the 

 synonyms and species of the Kcratospongia (Spong. Adriat. 

 Meeres, 1866, 2nd Suppl. p. 10), considered algoid, and there- 

 fore rightly observed that the genus should be suppressed. 

 I had also observed it in two or three instances, and had re- 

 garded it in the same light — that is, of the same nature as the 



