PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 13 
segment of the antenna is irregularly armed beneath with small spines 
or teeth, and in the male with a slender spine at the distal end. The 
eyestalk is armed with a minute spine or tubercle in front, and above 
with a small tubercle at the emargination of the cornea. The exposed 
surface of the ischium and merus of the external maxillipeds is armed 
conspicuously with marginal and submarginal spines, of which one on 
the inner edge of the merus is very long. 
The chelipeds in the male are stout and nearly twice as long as the 
carapax, including the rostral horns; the merus is a little shorter than 
the chela and triquetral, with all three of the angles thickly armed with 
very long and slender spines; the carpus is rounded externally, but 
armed like the merus; the chela is longer than the carapax, excluding 
the rostral horns, and naked and unarmed except by a few spines along 
the proximal part of the dorsal edge; the body is stout and swollen, 
and the digits slightly shorter than the body, nearly straight vertically 
but strongly curved laterally, very much compressed, grooved longitu- 
dinally on the sides and on the rather broad dorsal edge of the dactylus, 
and the prehensile edges crenately serrate and in contact throughout. 
In the female the chelipeds are only about once and a half as long as 
the carapax, including the rostral spines, much more slender than in the 
male, and armed with proportionally longer spines; and the chela is 
much shorter than the carapax, excluding the rostral horns; the body is 
searcely at all swollen, and is armed with slender spines along both 
edges and with minute spines or tubercles on the sides, and the digits 
are proportionally longer and narrower than in the male. 
The ambulatory legs are very long and slender, clothed to the tips of 
the dactyli with numerous curved setiform hairs which persistently re- 
tain mud and other foreign substances, and each is armed with a slender 
spine on the upper side of the distal end of the merus. 
In the male the abdomen is much broader relatively to the sternum 
than in Huprognatha rastellifera, and has a low tuberculiform elevation 
on each somite. The first and second somites are narrow, the third 
broadest of all, the fourth and fifth successively a very little narrower, 
the fifth fully twice as broad as long, and the sixth and seventh consol- 
idated as in Huprognatha and Collodes, together much broader than long 
and very broad and obtuse at the tip. The appendages of the first 
somite reach nearly to the tip of the abdomen, and their tips are stout 
and curved outward very strongly. 
The eggs are numerous, nearly spherical, and approximately 0.6™™ in 
diameter in alcoholic specimens. 
