1879.] 157 [Kingsley. 
tooth nearly three times as long as preceding one. Kyes moderate. 
Antennae about one-third the length of the carapax, the two distal 
joints of the peduncle subequal. External maxillipeds fringed with 
hairs, the surface granulate. Ischium of chelipeds minutely granu- 
late, with three spines on the inner margin, the third farther from the 
second than the second from the first, external margin distally 
emarginate, external distal angle with a short acute spine; carpus 
externally with several irregular raised lines, a small spine externally. 
Hand slender, nearly as long as the carapax, and ornamented with 
raised lines; of these there are two on ‘the upper surface, three on 
the inner, the lower being less distinct than the other two, and on the 
outer surface are two more, the lower being more distinct on the 
thumb but fading out about the middle of the palm. Fingers about 
as long as the palm, slender, and somewhat curved downward. Sec- 
ond and third pairs of feet compressed, subequal, fourth pair also 
compressed, the extremity of the dactylus reaching to the propodo- 
dactylic articulation of the preceding pair. Fifth pair equalling the 
fourth in length, the dactylus being a half longer than broad. 
Sternum nearly as long as broad, transversely but slightly convex. 
Abdomen of male slender, the sutures mostly indistinct, last seg- 
ment tapering, as long as broad, extremity rounded. Verges slender, 
their distal portion straight and reaching to the middle of the third 
segment of the sternum, or nearly to the extremity of the penult- 
imate segment of the abdomen. 
This species resembles C. pleuriticus Ordway, more closely than it 
does any other west coast form. It differs however in the following 
particulars. ‘The external teeth of the front are more prominent, 
the antero-lateral teeth are more crowded together, the fissures be- 
tween them being nearly closed, the male verges are larger and with 
the extremities straight, and the antero-lateral margin is but very 
slightly arcuate. 
Several specimens from the Gulf of Fonseca, west coast of 
Nicaragua. A male gives the following measurements. 
Length of carapax, 21.3 mm.; breadth, 45 mm.; ratio, 1: 2.11. 
I have found it very difficult to distinguish the species of this genus 
as the published descriptions are almost wholly comparative, and 
unless one has a large proportion of the species, determination is by 
no means an easy matter. 
