Boone, Crustacea, Cruises of *' Eagle" and "Ara," 1921-28 21 



Copepoda. 

 Pontella plumata (Dana). 



About a dozen females, dredge down 300 fms., seven miles S. W. 

 of Cape Malo, Panama, March, 1928. 

 Pandarus hicolor Leach. 



About 36 specimens, parasitic on shark, taken off Jicaron Island, 

 Panama, January 27, 1928; seven specimens from tiger shark, cap- 

 tured in West Indian seas, March 23, 1925. 



SYSTEMATIC DISCUSSION. 



ANOMURA. 



Family : PAGURIDAE. 



Subfamily: Pagurinae. 



Genus : PETEOCHIEUS Stimpson. 

 Petrochirus bahamensis (Herbst). 



Plate 1. 



Diagnostic characters: The largest of the marine hermits of the 

 West Indian faunal region. Chelipeds subequal or sometimes mod- 

 erately unequal, covered with an arrangement of granules, consisting 

 of three in each group. 



Type : Herbst 's type was taken in the Bahama Islands, inhabiting 

 the shell of "Buccino magna variegato Lifter 359, No. 12," and was 

 deposited in the Berlin Museum. 



Distribution : Southern Florida to Brazil. Littoral. 



Material examined: Two very large specimens taken in dredge, 

 Florida Reefs, 1923, by the ''Ara," WiUiam K. Vanderbilt, com- 

 manding. 



Technical description: Precervical region of carapace shield- 

 shape, widest anteriorly, the dorsal surface slightly convex, with sev- 

 eral scattered, coarse pits and clusters of setae; the frontal margin 

 bears a blunt, median triangular tooth, which is no farther advanced 

 than the similar submedian pair which occur between the bases of the 

 eye-stalk and the external antennae; outside of the submedian point 

 the frontal margin is excavate at the base of the antennal peduncle, 

 terminating at the lateral margin in a blunt tooth. The postcervical 

 region of the carapace widens posteriorly with the postlateral regions 

 lobed ; the encasing membrane is very tough, leathery, including the 

 median region; a series of six to eight longitudinal lines or wrinkles 



