No. 1. — Reports on the Results of Dredging, under the Supervision 

 of Alexander Agassiz, on the East Coast of the United States, 

 during the Summer of 1S80, by the U. S. Coast Survey Steamer 

 "Blake" Commander J. E. Bartlett, U. S. N., Commanding. 



(Published by peiiuission of Carlile P. Patterson and J. E. Hilgakd, Supts. 



U. S. Coast and Geodetic Survey.) 



XVII. 

 Report on the Crustacea. Part I. Decapoda. By Sidney I. Smith. 



The part of the following report relating to the Maci-ura was ready 

 for the printer before Alphonse Milne-Edwards's Description de quelques 

 Crustac'es Macroures provenant des grandes profondeurs de la Mer des 

 Antilles (Annsdes Sci. Nat., Zool., 6°" serie, XL No. 4, 1881) was received, 

 so that all the references to it have been added subsequently. The new 

 species in this and some other recent papers of Milne- Edwai'ds, and in 

 Bates's recent paper on the Penaeidea, are so inoperfectly characterized 

 that in several cases I have found it impossible to determine, with any 

 approximation to certainty, whether or not they are identical with 

 species described in the following pages. I have endeavored, however, 

 to make the descriptions and figures of the species here described so 

 complete, that subsequent investigators will not labor under a similar 

 difficulty in regard to them. 



BRACHYURA. 



MAIOIDEA. 

 Amathia Agassizii, sp. nov. 



Plate II. Figs. 2, 3. 



Resembles A. Carpentcri Norman (figured by Wyville Thomson, Depths 

 of the Sea, p. 175, 1873), but has shorter rostral horns and more numerous 

 spines upon the carapax. 



The carapax Ip sub-triangular, excluding spines and rostral horns, nearly 



VOL. X. — NO. 1. 1 



