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THE VOYAGE OF H.M.S. CHALLENGER. 
joint (in Iliacantha intermedia ) longitudinally sulcated ; merus as usual triangulate ; 
exognath rather narrow, with the exterior margin straight. Chelipedes slender and rather 
long, with the merus sub cylindrical and granulated ; palm slender, narrowing distally 
and somewhat contorted, so that the fingers open vertically ; the fingers (as in Ilia) are 
very slender, and are armed with fine, usually spinuliform, teeth. Ambulatory legs 
slender and of moderate length ; tarsi styliform. 
From Hia this genus differs in having but three posterior spines on the carapace, and 
from Myropsis in that the fingers open in a vertical and not in a horizontal plane. 
To the species described by Stimpson, Iliacantha globosa and Iliacantha sparsa, 
dredged in the Florida Straits in 30 to 60 fathoms, I have to add a third, Iliacantha 
intermedia, obtained by the Challenger Expedition at Bahia, in shallow water. 
Iliacantha intermedia, n. sp. (PI. XXVI. fig. 3). 
This species is distinguished from the West-Indian Iliacantha subglobosa, Stimpson, 
and Iliacantha sparsa, Stimpson, 1 by the length of the dactyli of the chelipedes, which 
in Iliacantha subglobosa considerably exceed, but in Iliacantha intermedia do not 
attain the leugth of the palm, and by the form of the postero-lateral spines or teeth 
of the carapace, which in Iliacantha intermedia are flattened and triangulate ; but in 
Iliacantha sparsa are similar in shape to, and more than half as long as, the posterior 
median spine. 
The carapace is moderately convex, longer than broad, and is everywhere very 
distinctly and evenly granulated ; the antero-lateral margins, at the hepatic regions, 
are bluntly angulated ; at some distance behind the hepatic angle there is another 
slight angular projection, as in Iliacantha subglobosa. The median and posterior spine 
of the carapace is prominent and acute, and very slightly recurved at the distal 
extremity ; the lateral spines or teeth are flattened and triangulate, and rounded at 
the apices. The front (as seen in a dorsal view), projects slightly beyond the eyes ; 
it is concave above, truncated in front, with the anterior margin nearly straight. The 
orbits are small, without fissures in the upper margin ; the endostome is strongly 
longitudinally ridged ; the ridges define the lateral channels (pterygostomian channels 
of Stimpson), which terminate distally in three strong spiniform teeth. The sternum 
is evenly granulated ; the post-abdomen (in the young male), has the segments, except 
the two first and the last, coalescent, and is granulated at and near the base. The 
ischium-joint of the endognath of the outer maxillipedes is longitudinally sulcated on 
its outer surface, which is nearly smooth ; the merus-joint is triangulate, acute, much 
shorter than the ischium, and strongly granulated on the outer surface ; the exognath 
is externally strongly granulated, with the exterior margin nearly straight ; its rounded 
1 Bull. Mus. Comp. Zool., vol. ii. pp. 155, 156, 1870. 
