Mr. H. J. Carter on Freshwater Sponges. 101 
the larger size of the “spherical cells” containing the germs, and 
their comparative tenacity, so that even in the broken section 
after desiccation these contents present a granular appearance 
instead of the usual homogeneity, from the unruptured state 
of these cells. 
Through the great kindness of Dr. Vejdovsky I am in 
possession not only of a copy of his publications on the Fresh- 
water Sponges of Bohemia, but of specimens mounted and 
unmounted of Ephydatia amphizona and Lrochospongilla eri- 
naceus, so that I am able to confirm the interesting facts 
which he has stated and illustrated respecting these sponges. 
While on this subject, I would add that on the 29th of 
November last I received for examination some specimens of 
the bottom-sediment of some lakes near Pictou, in Nova 
Scotia, from Mr. A. H. McKay, B.A., B.Sc., Principal of the 
Pictou Academy ; and in that of “ Karltown Lakes” I found, 
besides spined skeletal spicules, birotulates identical with 
those of Meyenia Leidii, together with others like those of 
the North-American form of Spongilla lacustris and those of 
the statoblasts &c. of Mr. Potts’s ? Meyenta cratertformis, so 
that, in a geographical point of view, the freshwater species 
of Pennsylvania are in all probability to be found also in 
Nova Scotia. 
P.S.—Since the above was written I have also received from 
Mr. Henry Mills, of Buffalo, N. Y., a letter dated 25th De- 
cember last, in which he states the same fact of some of the 
North-American freshwater sponges as that from Bohemia, 
described and illustrated above by Dr. Vejdovsky under the 
name of Ephydatia amphizona. Mr. Mills’s letter is accom- 
panied by two specimens, viz. one from Ischua Creek, Catta- 
rangus Co., N. Y., and the other from Bear Creek, Iowa, in 
which I have been able to confirm what he has stated. He 
also notices a third locality, viz. the Calumet Creek, sixteen 
miles south of Chicago, adding that “ all these have the bi- 
serial arrangement of the birotules in the outer coat of the 
statoblast.”’ 
Of what specific value the bi- and triserial rows of biro- 
tulates may be I am not prepared to say, as I find them also in 
the statoblasts of Meyenia fluviatilis of Bombay, wherein the 
crust of those that are fully developed is very thick, and often 
shows three birotulates end to end, although not so numerous, so 
regular, or so uniform in arrangement as in the innermost row ; 
indeed [ should say the outer ones were scattered, particularly 
those of the outermost row—recalling very much to mind the 
