ASTRORHIZIDAE—IRIDIA; HALIPHYSEMA. 19 
Isles. There are, therefore, one or more tropical species of the 
form described here in both the Indo-Pacific and the West Indian 
regions. In general it may be said that the faunas of these two 
regions are much more nearly allied than are either of them to the 
fauna of the British Isles. 
In the living specimens which I had under observation it was 
noted that the pseudopodia followed out the spicules of the “capit- 
ulum” and then off into the water, while others came out appar- 
ently through interstices of the cylindrical part. The pseudopodia 
were all very fine and clear, with few branches and little anastomos- 
ing, as shown by Moebius in his figures. The spicules of the 
“capitulum” were variously placed, some with the point of the 
spicules out, others with a rounded end outward. ‘These spicules 
were usually entire and more or less covered by a film of foreign 
material, evidently brought in by the contracting of the pseudopodia. 
In the specimen figured (fig. 1), an appendage of a copepod had been 
inserted among the spicules and extended out to several times the 
length of the spicules. Moebius (loc. cit., pl. 1, fig. 4) shows a 
specimen with a peculiar body standing up above the spicules. 
In this connection it seems fitting to call attention 
to the observations of Heron-Allen and Earland 
on Marstpella cylindrica H. B. Brady (Journ. Roy. 
Micr. Soc., 1912, p. 388). They show there that a 
specimen from the Faroé Channel found by Harland 
had a capitular end very similar to that figured here. 
It may be questioned whether that specimen is really 
“the perfect organism’’ referred to by the authors, 
or whether it may not have originally had a base 
and been really a species of Haliphysema. Inshort, 
is not Marsipella cylindrica H. B. Brady really 
Haliphysema cylindrica (H. B. Brady)? Instead of 
modifying Norman’s original description of Marsi- 
pella to include the capitular head and cylindrical 
I" body, it seems very probable that a base will later 
| be found for the Marsipella cylindrica. The type 
i 
| 

\ species of Marsipella, M. elongata Norman, is evi- 
\ dently a very different organism from M. cylindrica, 
mi the fusiform shape of M. elongata and the tapering 
/ necks at either end from a body composed largely 
# of sand-grains making it seem in its general relations 
en very different from that found by Earland. 
nd \ Fic. 1.—Haliphysema advena, new species. X25. Showing general out- 
line of specimen, a broad basal portion, slender cylindrical column, and 
mea capitular “‘head.’’ The long, projecting body is an appendage of a 
copepod which was used among the usual sponge-spicules. 
