SCYPHIDIüM LONGISPINA. 31 



that they contained a nucleus which was pressed against the 

 wall. Cases also came under my observation, in which the 

 spheres in question showed a close approach, in size as well as 

 in the character of the contents, to the thesocytes which 

 are filled u]) with the fat-like product. So that, I am inclined 

 to think that they represent but an early stage in tlie develop- 

 ment of thesocytes. 



In sections of one (the larger) of the two young individuals 

 found attached to the prostalia of the specimen, I find the theso- 

 cytes by no means so copiously present. On the other hand, T 

 see in them an al)undance of peculiar bodies, the like of which 

 I have not met with in the large specimen and the nature of 

 which remains perfectly dark to me. The bodies consist of 

 numerous, thin, deeply stained filaments, which reach up to 

 5Ô ,« in length and are arranged either radially so as to present 

 an irregularly star-like appearance or in brush-like bunches diverg- 

 ing from a point (PI. II., fig., 15). The filaments are sometimes 

 nearly straight and needle-like ; sometimes gently lient or wavy. 

 The general appearance reminds me of the groups of stearin and 

 margarin cr3^stals, which A. Letellier* obtained from the alco- 

 holic extract of the organ of Bojanus. But the stainability of 

 the filaments at once excludes the idea of their beinof crvstals. 

 Possibly we have here to do with something which is certainly 

 not identical with, but is allied to, the groups of rod-like 

 bodies I have met with in Acanthascus cactus and Euplectella 

 marshalU (Contrilx I., p. 180) ; at any rate, they all seem to be 

 bodies foreign to the sponges. 



* A. Letellier. Fonction urinaire chez les ]\IolliJSf|nes acéphale^;. — Arcli. Zool. Expér. 

 T. V. 2me Serie, p. 48 ; PI. I., figs. 6, 7. 



