560 THE VOYAGE OF H.M.S. CHALLENGER. 



"With reference to this species Mr. J. S. Kingsley further remarks, 1 " In the Annual 

 Report of the U. S. Geological and Geographical Surveys of the Territories for 1874, 

 p. 388, Mr. Ernest Ingersoll says — 'From the pond mentioned, between camps E. and F. 

 [in south-western Colorado] a small crab was brought home, which Professor I. S. Smith 

 pronounced to be a true marine form, belonging to the Astacidose (sic).' Professor Smith 

 informs me that the specimen shown to him was undoubtedly Alpheus minus, and 

 thought it more than probable that some confusion of localities or mixture of specimens 

 had occurred, but, on the other hand, Mr. Ingersoll is as positive as it is possible to be 

 that the specimen was found in the pond mentioned." 



Alpheus spiniger, Stimpson (PI. C. fig. 3). 



Alpheus spiniger, Stimpson, Proc. Acad. Nat. Sci. Philad., p. 110, January I860. 



Body robust, coxal plates of the pleon as deep as the lateral walls of the carapace, 

 rostrum acute, straight, reaching beyond the first joint of the peduncle of the first 

 pair of antennas, and separated by a groove on each side from the orbital lobes, which 

 are armed with a sharp and straight tooth that is about half the length of the rostrum. 



First pair of antenna? having the first joint a little longer than the second, and 

 furnished with a stylocerite that is equal to it in length. The flagella are subequal, 

 neither being much longer than the peduncle. 



The second pair of antennae has the basal tooth reaching nearly as far as the 

 extremity of the rostrum, and the scaphocerite as long as the peduncle of the first pair. 



The second pair of gnathopoda has the terminal joint extending beyond the peduncle 

 of the second pair of antennas, and has the margins fringed with hairs. 



The first pair of pereiopoda (figs. 3k, 3k') has the larger hand upon the right side ; 

 carpos small; propodos ovate, smooth, thick and tapering; pollex hollowed, with 

 the lateral margins elevated; dactylos rounded at the apex and posteriorly produced on 

 the inner side to a stout tubercle, which, when the hand is closed, is impacted deeply 

 into a cavity at the posterior extremity of the pollex. The smaller or left chela 

 (fig. 3k') is normal in form and much resembles that of a species of Brachyura; it 

 has the pollex and dactylos slightly curved, closely impinging, parallel, and about half 

 the length of the palm. The second pair of pereiopoda is not much longer than the 

 third, it has the four distal articuli of the carpos sitbequal in length, and the first 

 nearly as long as the other four. The third, fourth and fifth pairs are subequally 

 robust, the anterior being the most and the posterior the least so. The carpos lias 

 the upper distal angle produced to a blunt tooth or process, which is most conspicuous 

 on the anterior pair and least so on the posterior. The propodos is slightly curved and 



1 Proc. Acad. Nat. Sci. Philad., p. 14, August 1878. 



