M. C. Semper on Euplectella aspergillum. 29 



endeavouring to bring the animal in all positions before some 

 of the larger openings in the terminal disk, as I could not de- 

 stroy the sponge itself. The two Palcemonidce^ on the con- 

 trary, were always too much injured, in all the specimens which 

 then came under my inspection, to allow them to be drawn 

 under such difficulties. As I am not at the moment able to 

 prepare drawings of the Crustacea, of which I have several 

 specimens now before me, I must content myself for the pre- 

 sent with a short description, which I hope to follow speedily 

 with a more accurate one, accompanied by figures. 



j:Ega s^ongiophUa^ n. sp. 



The head is rounded off in front, and strongly bent down- 

 wards. The two eyes are very large, but do not touch each 

 other, leaving the forehead produced into a small point 

 between them ; the broad basal joints of the antennae origi- 

 nate at the sides of the forehead. The first joint of the upper 

 antennae is nearly quadrangular, twice as broad as the length 

 of the frontal point; the second joint somewhat smaller; the 

 third joint is thin and cylindrical, and reaches to the middle 

 of the eyes ; the terminal filament is many-jointed, and does 

 not reach quite to the hind margin of the first thoracic seg- 

 ment. The inferior antennae commence with two short but 

 broad joints ; the three following long and cylindrical joints 

 reach nearly to the end of the inner antennge ; and the small- 

 jointed terminal flagellum goes to the commencement of the 

 abdomen. The epimera of the first seven segments of the 

 body are large and lanceolate. The first segment of the 

 postabdomen is the narrowest, and the penultimate the 

 broadest. The last abdominal segment is straight-margined 

 anteriorly, strongly curved behind. The lamellae of the 

 abdominal swimming-feet are acutely oval, and do not pro- 

 trude beyond the hinder margin of the last segment. 



The description of the Palaemonid I will reserve for the 

 present, as I hope soon to be able to make a better one, from 

 perfect specimens preserved in spirits, than would be possible 

 now from the dried and partially destroyed animals. 



In conclusion, I will only make a few remarks upon the 

 Sponge itself. Bowerbank's censure of Owen has been duly 

 refuted in the above-mentioned article by J. E. Gray ; but 

 when Gray unconditionally defines the Sponge described by 

 Quoy & Gaimard as identical with that from the Philippines, 

 I must declare myself opposed to this view, until accurate in- 



