REPORT ON THE ANOMURA. 159 



regard the institution of the former genus as other than questionable. The two occur in 

 similar localities and at corresponding depths. The two species which I previously placed 

 in a separate subgenus intermediate between Elasmonotus and Munidopsis, although in 

 some respects peculiar (as in the form of the rostrum), I have now, on second thought, 

 referred to Elasmonotus; at the same time, I cannot see sufficient reason for the 

 separation of the form which Professor S. I. Smith has designated Anoplonotus. 



Elasmonotus armatus, A. Milne-Edwards (PI. XIX. fig. 5). 



Elasmonotus armatus, A. Milne-Edwards, Bull. Mus. Comp. Zool., vol. viii. No. 1, p. 61, 1880. 



Habitat. — Station 23, off Sombrero Island, West Indies ; depth, 450 fathoms ; 

 bottom, Pteropod ooze. A female with ova, and a young individual. 



Station 24, off Culebra Island, West Indies ; depth, 390 fathoms ; bottom, Pteropod 

 ooze. Two females, one of which bears ova, and a male. The largest specimen (a female) 

 measures as follows : — Length of body 23 mm., of carapace (including rostrum) 13'3 

 mm., of chelipede 26 mm., of first ambulatory leg 20 mm. 



The surface of the carapace is faintly rugose, and two minute tubercles are present on 

 th.e rather convex gastric area ; the cardiac area is circumscribed, and a shallow groove 

 passes transversely across its surface. The lateral margins of the carapace are raised, 

 and form a prominent rounded rim on each side, which terminates anteriorly in a short 

 acute spine. The rostrum is long, narrow, and slightly upturned, with its apex acuminate, 

 and a slight constriction is present towards the base. The ocular peduncles are slightlv 

 elongated, but do not terminate in spines. The merus of the external maxillipedes is 

 armed with two long and subequal spines on the proximal half of the inner margin, and 

 the inner margin of the ischium is prolonged distally into a spine. The chelipedes are 

 slender and elongated, with only a few short spinules present at the distal ends of the 

 merus and carpus, and one or two on the inner surface of the merus ; the fingers are 

 stout, and excavated inferiorly, wdtli a slight thickening towards the apices. The 

 ambulatory limbs are slender, and provided with a single spinule at the anterior and 

 distal end of the merus ; the dactyli are of large size, and a series of horny spinules is 

 articulated to the posterior margin. The second and third abdominal segments are 

 strongly carinated transversely. 



The " Blake " specimens were taken off Frederickstadt, AVest Indies, at a depth of 625 

 fathoms. 



