138 BULLETIN OF THE 



length of meros-joint of cbeliped, 0.22 ; length of hand, 0.26 ; breadth of 

 hand, 0.12 inch. 



The specimen was taken off Conch Reef in 34 fathoms. 



CANCROIDEA. 



Family CANCRIDAE. 



Subfamily XANTHINAE. 



Actaea nodosa Stm. 



Actaea nodosa Stimpson, Notes on N. American Crust., p. 75. Desbonne 

 et Schramm, Crust, de la Guadeloupe, p. 25. 



Dredged January 16, 18G9, west of the Tortugas, in 35 and 37 fathoms. 



Actaea setigera Stm. 



Xantho seliger II. Milne-Edwards, Hist. Nat. des Crust., I, 390. 

 Actaea sctiyera Stimpson, Notes on N. American Crust., p. 51. A. Milne- 

 Edwakds, Nouv. Arch, du Muse'um d'Hist. Nat., I, 271 ; pi. xviii, fig. 2. 



Found on the Reef at Cruz del Padre, Cuba. 



Carpoporus nov. gen. 



Carapax suhhexagonal, nearly as long as broad; antero-lateral margin 

 armed with three small teeth (in a line which conducts beneath the orbit 

 anteriorly), and drawn in posteriorly, the greatest breadth of the carapax 

 being at the middle tooth ; postero-latcral shorter than the posterior mar- 

 gin ; facial region very broad ; front prominent. Orbit circular, without 

 teeth below, except two or three minute spiniform denticles on the 

 margin ; fissures of outer and inferior margins obsolete. Basal joint of 

 the external antennas narrowing forwards, reaching the front, and passing 

 well into the hiatus of the orbit, nearly as in Euxanlhus ; movable part 

 of* the antenna? very small. Chelipeds, when retracted, having a large 

 hole between the carpus and hand above for the passage of water to the 

 afferent branchial apertures. Third, fourth, and fifth joints of the 

 abdomen in the. male soldered together ; terminal joint as brOad as long. 



This genus differs from Xantho in its external antennas ; from Euxan- 

 thus in the narrowness of the carapax ; from Polycremnus in its five- 

 jointed male abdomen ; and from Halimede and Medaeus in the want of 

 conspicuous fissures and teeth on the margin of the orbit. 



It is very peculiar in the perforation of the retracted chelipeds, recall- 

 ing a similar perforation of the chelipeds of Echinocerus foraminatus, in 

 which, however, it occurs between the carpus and meros. 



