South-Russian Spongillidae. 59 



4. From the river Siewieruyj Daniec, Gov. Cliarkow. 



5. From Lake Wielikoje (Circle Lebieclin), Gov. Gharkovv. 

 Offering- my best thanks to the sender of these sponges, 



I now communicate the results of my investigations upon 

 them. 



These results are as follows. The Spongillse of these five 

 localities represent three species, namely : — 



A. Spongilla lacustris. 



B. Meyenia [Ephydatia) fluviatilis. 



C. Dosilia (?) Stepanowiij n. sp. 



The first two of these * I have only briefly described ; but 

 the third, as a form hitherto unknown to science, has received 

 as accurate and detailed a description as possible. 



8pong{lla lacustris^ Carter, occurs in very thin lamellte, 

 coating in spots or cones the leaves of Acorus Calamus and 

 Que7x.us s]). ; they are evidently quite young and undeveloped 

 specimens, in which I have consequently found no gemraules. 

 The skeleton-spicules are 0'224-0"130 millira. long, O'OIO- 

 0*002 milHm. thick f. The size of the parenchyma-spicules 

 varies between 0*050 and 0*060 millim. in length, and 0*002 

 and 0-004 millim. in thickness. These spicules perfectly 

 agree with those described by me {loc. cit.). 



Among the spicules such deformities frequently occur as I 

 have already described and figured {I. c.) ; but among the 

 most peculiar are the clavate and pin-shaped spicules, the 

 heads of which are sometimes quite smooth and rounded, but 

 sometimes variously misshaped, or furnished with small 

 spines |. 



Localities. Daniec, Kolomak. 



The Meyenia Jluviatilis, auct., agrees perfectly with that 

 described by me {l. c. p. 13). I have before me four frag- 

 ments of a large, fully developed sponge and a couple of 

 smaller ones. In all numerous gemmules are present. The 

 fragments belong to cushion-like sponges ; the smaller sponges, 

 on the contrary, are growing round a stem, 8 millim. thick, of 

 Arundo sp. 



Localities. Lake Lebiedin, river Udy. 



* See Dybowski, " Studien iiber die Slisswasser-Schwamme des Russi- 

 schen Reiches," in Mem. Acad. Sci. St. Petersb. ser. 7, tome xxx. no. 10, 

 p. 6, tab. i. figs. 4, 6, 7, and p. 13, tab. i. iig. 3, and tab. ii. fig. 9. 



t In my memoir (I. c.) p. 10, column 1, line 4 of the measurements, 

 0-009 is erroneously printed instead of 0-002, and in column 3, line 6, 0-028 

 instead of 0'002, 



X The figures necessary for the more ready intelligence of all the_ de- 

 scriptions here given, I have prepared with the aid of a Hartnack's prism, 

 and will publish them when opportunity serves. 



