11 



the cast of that of a Dodo, and pointed out a general resem- 

 blance between them. Dr. Cabot remarked that the head 

 of the Dodo strongly resembled that of some of the Doves. 



Mr. Desor stated that among the various animals that he 

 had procured lately by dredging in Boston harbor at a depth 

 of twenty-five or thirty feet, there were many specimens of 

 a small Star-fish, probably a new species, of the genus Echi- 

 naster, nearly allied to the European E. sanguinolentus. 



Several specimens of these star-fishes carried around and be- 

 fore their mouths large bundles of small yellow bodies, of the 

 size of small pins' heads, which were the eggs. An interesting 

 fact is the existence of a strong maternal instinct in these animals. 

 On removing the eggs from the mother^s embrace, she was seen 

 to move at once directly towards them, and clasp them again. 



On examining the eggs under a microscope, it was ascertained 

 that each egg contained a large, opaque, yellow sphere, which 

 was surrounded by a transparent fluid, similar to that which is 

 found in the eggs of the MoUusks, and being by no means of an 

 albuminous character. On escaping from the eggs the spheres 

 began almost immediately to contract at one extremity, so as to 

 form a sort of peduncle. It was no longer a simple yolk, but an 

 embryo. The peduncle became more and more marked, and 

 after a short time (commonly the first day) the embryo had as- 

 sumed a form very similar to that of a mushroom. In the mean 

 time there could be seen a distinct separation of the embryo into 

 two layers, an external one, more or less transparent, and an in- 

 ternal one, more opaque. Both were composed of very minute 

 nucleated cells, some having even a nucleolus. 



In many cases the division into two zones may be perceived, 

 even when the embryo is still enclosed in its shell ; showing that 

 in these lower animals the hatching does not occur at a fixed 

 epoch of development, but that it may be considerably accelera 

 ted or retarded according to circum.stanees. 



Dr. Storer announced the reception, from Capt. Atvvood, 

 of a Shark, captured at Provincetown, of a species which 

 he at present considered new. It might perhaps be the 

 same as one described by Dr. Wood, of Portland ; but as 



