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 Palemonide, 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. 
Aiga spongiophila, 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 antenne origi- 
nate at the sides of the forehead. The first joint of the upper 
antenne 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 antennes commence with two short but 
broad joints ; the three following long and cylindrical joints 
reach nearly to the end of the imner antennz ; 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 lamelle 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 Palemonid 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- 
