G. GENERAL NATURAL HISTORY AND ZOOLOGY. 225 



INJECTION OF CRINOIDS WITH SILICA. 



As bearing upon certain questions connected with the true 

 condition of Eozoon, Dr. Dawson, of Montreal, calls attention 

 to the occurrence of crinoids and other unmistakable fossils, 

 with their pores or cavities filled with a silicious substance 

 which completely penetrates their most delicate structures, 

 and which proves on examination to be a hydrosilicate allied 

 to jollyte. 12 A, June 29,163. 



EAEE ECHINUS. 



In an appendix to a report published by the Museum of 

 Comparative Zoology on the echini collected by Pourtales, 

 mention is made by Mr. Alexander Agassiz of an interesting 

 species of this group, obtained during the Coast Survey ex- 

 ploration of the Gulf Stream in 1868 and 1869. This, at the 

 time the preliminary report was written, could not be identi- 

 fied by Mr. Agassiz ; but he has since then been able to as- 

 certain that they belong to a genus named Kerioaphorus, the 

 type of which had been drawn up on a fishing-line from a 

 depth of about seven hundred feet. It is peculiar on account 

 of its long curved spines, which resemble the antenna? of a 

 certain family of beetles. 



BRYOZOA AND PARASITIC CRUSTACEA. 



Professor Claparede has made some interesting communi- 

 cations to the Society of Physics of Geneva upon certain ma- 

 rine invertebrates. One of these has reference to the Bryo- 

 zoa, a group of animals found in fresh water and salt, and re- 

 sembling polyps in living in associations, but which are dis- 

 tinguished from them in their external characters, and espe- 

 cially in the absence of any radiated structure. He has in- 

 vestigated this group with special reference to the relations 

 which exist between the different individuals of the same "as- 

 sociation relations of nutrition by the intermediation of 

 pores which permit the passage of the nutritious liquid from 

 one individual to another, and the nervous relations estab- 

 lished by a colonial nervous system, as already pointed out 

 some years ago by Mr. Fritz Miller. On different points of 

 the group of individuals there are frequently found fixed bod- 

 ies called Avicularia, which M. Claparede considers as rudi- 



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