DECAPOD AND OTHER CRUSTACEA 4 



The crustacean collection, though not large, contains several novel- 

 ties : a new species, Thalamita rooscvclti; and two new subspecies, 

 Callianidea lacvicauda occidentals and Crangon hazvaiiensis clipper- 

 toni. A West Indian species, Callianassa hartmeyeri, earlier reported 

 by Hult (Arkiv Zool., vol. 30A, No. 5, p. 7, text figs. 1-4, pi. 1, figs, 

 ia, ib, 1938) from the Galapagos, was found at Socorro Island. 

 Brachycarpus biunguicidatus, another West Indian species, originally 

 described from Bermuda and well known in the Mediterranean, with 

 also a single record from the Red Sea, rather surprisingly turned up 

 in the Clipperton Island material, a first truly Pacific record, for this 

 species. An Ogyridcs, the first representative of the genus from the 

 west coast of America which was taken at Punta Gorda, as well as 

 a Crangon from Socorro, a possible new variety of Crangon para- 

 crinitus from Clipperton, and several species of Pclrolisthcs, have not 

 been described for want of 'adequate material of each of them. Other- 

 wise, there is a small residuum of very fragmentary specimens, 

 juveniles, and larval forms, not satisfactorily determinable, that are 

 not included in this report. 



In this list we are able to enumerate approximately 100 different 

 decapods, including 4 species of porcellanid or flat crabs ; in addition, 

 there is 1 leptostracan, a barnacle, and 8 species of copepods, making 

 a total of 110 different kinds of Crustacea. The greatest number of 

 species listed for any one station was 42 from Old Providence ; next 

 in order, 17 from Sulivan Bay, James Island, Galapagos. 



Of the new forms described in this paper, two were collected at 

 Clipperton Island, where, so far as I have been able to ascertain, 

 little or no marine carcinological collecting has ever been clone before. 

 This coral atoll, which is unique in American waters, supports a 

 remarkably interesting marine fauna, inasmuch as 7 of the 18 spe- 

 cifically identified species have strong Indo-Pacific ties, and 1, Brachy- 

 carpiis biunguicidatus, a less strong tie. Indeed, four of those seven 

 species are identical with species known from Hawaii and beyond. 



4 The amphipods and isopods will appear as separate reports by Clarence R. 

 Shoemaker and J. O. Maloney, respectively, of the Division of Marine Inverte- 

 brates, U. S. National Museum. 



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