250 Dr. M. DjbowskI ow Dosilia Stepanowii. 



material then in my possession. In order to complete the 

 knowledge of this fine and exceedingly interesting sponge I 

 propose now to give as accurate a description as possible of 

 the gemmules. The figures that I have prepared will appear 

 shortly in the publications of the Society of Naturalists of the 

 University of Charkow. For tlie material upon wiiich my 

 investigations are based I am indebted to the kindness of my 

 friend and collahorafeur Prof. P. T. Stepanow. 



The above-mentioned material is from the Government of 

 Ciiarkovv, and consists of two small spiiit-specimens furnished 

 witli gemmuies. 



One specimen in which the gemmules exist within the paren- 

 chyma is a fragment of a larger sponge. This sponge is 

 from Lake WieUkoje and was presented to tlie University 

 Museum by a student, M. Radkiewicz. 



The other specimen is a small, nearly perfect sponge, 

 coating the surface of the leaf of a tree in a very thin layer. 

 In this the gemmules are placed in a group at the base of the 

 sponge, and consequently on the surface of the leaf. This 

 latter specimen Avas found (on August 5, 1883) by another 

 student, M. J. W. Riabinin, in a small hike, coiuiected with 

 the river Daniec, in the neighbourhood of the village of 

 Kotschetvok. 



lleferring to my previous writings (/. c.) for the characters 

 of tlie sponge Dosilia'} Stejjanowiij I now j)ass to the descrip- 

 tion of the gemmules. 



The gennnules are spherical, more or less dark horny- 

 brown coloured v^esicles, 0'3-0"5 millim. in diameter, in which 

 the following parts may be distinguished : — 



1. Tlie gemmula-capsule ; 



2. The coating-layer ; 



3. The pore; 



4. The pore-appendage ; and 



5. The germinal matter. 



If we examine under the microscope (Hartnack obj. no. 4) 

 a section passing through the whole gemmule (including the 

 pore), or an entire (sufficiently transparent) gemmule in pro- 

 tile (which in this case is much better), all the above parts, to 

 the description of wliich we shall now pass, may be very dis- 

 tinctly recognized. 



1. The Gemmula-capsule (Vejdovsky's '^ Chitinmera- 



bran "* ; Carter's '' cliitinous coat "f). ' 



The capsule of the gemmule consists of a structureless, 



* r. Vejdovsky, "Die Siisswasser-Schwamme Bohmens/' in Abbandl. 

 k.-k. Bolim. Gesellsch. d. Wiss. ser. 6, Bd. xii. p. 33. 



t H, J. Carter, Ann. k Mag. Nat. Hist. l%&>, pi. xiv. fig. 2 &c. 



