88 PfiOCEEDINGS OF UNITED STATES NATIONAL MUSEUM. [188r>. 



The specimens from tliese several localities exhibit considerable vari- 

 ation in structure, though there is no difficulty in referring them all to 

 this species. 



Echinocyamus pusillus, Vau Ph. - 



Several dead specimens were obtained at station 2150; latitude 13° 

 34' 45" N., longitude 81° 21' 10" W., 382 fathoms (7116). 



Echinanthus rosaceus, Gray. 



Numerous fine specimens of this species were dredged in shallow 

 water at St. Thomas (8419, 8420). One living specimen was obtained 

 at San Antonio, at the western extremity of Cuba (8418), and one dead 

 specimen at Key West, Fla. (8417). 



Mellita sexforis, A. Agassiz. 

 A single living specimen was obtained at Old Providence Island 



(8423). 



Encope emargiiiata, L. Agassiz. 



A fine series of specimens in good condition was collected at Saba- 

 nilla (8421, 8422). 



Homolampas fragilis, A. Agassiz. 



Two specimens, apparently belonging to this species, were obtained 

 at station 2117; latitude 15° 24' 40" K, longitude 63° 31' 30" W., 683 

 fathoms (8397). One is comparatively perfect, the other very much 

 broken. The perfect specimen is much larger than any which Mr. 

 Agassiz seems to have had the opportunity of examining, measuring 

 26 ™™ in longitudinal diameter, and presents several characters resem- 

 bling more those of R.fulva* than would be indicated by Mr. Agassiz's 

 original description of this species. 



There are four genital openings placed rather more closely together 

 than represented in Mr. Agassiz's figures of fulva, and, for the most 

 part, two perforations instead of one to each ambulacral plate on the 

 dorsal side. There are no large primary tubercles and spines in the 

 posterior interambulacral area, but in the posterolateral interambu- 

 lacra, on each side, there are six such tubercles, having a somewhat 

 concentric arrangement, in three rows, with reference to the abactinal 

 system, there being one spine above, two in the second row, and three 

 in the lower. These tubercles are quite closely placed, especially those 

 of each row, and several of their spines, all of which are strongly curved, 

 reach to or slightly beyond the posterior end of the test. 



In the anterior interambulacra there are also six large tubercles, two 

 arranged vertically above and two pairs below. Their spines are but 

 slightly smaller than those above described. The entire arrangement 

 of primary tubercles is much more anterior than in fulva, as figured by 

 Mr. Agassiz, being included within the anterior two-fifths of the test in 



A. Agassiz, Report on the Echinoidea of H. M. S. Challenger, 1881, p. 164, 



