A. E. Verrill — Revision Genera and Species of StciT^shes. 217 



foui'th adambulacral, has three plates in one series and two in the 

 other. Beyond this the plates are few and irregular. 



The adambulacral plates are broad and roundish, the proximal ones 

 quite oblique ; their furrow edge projects over the furrow and bears 

 a row of 10 to 12 small, slender-, acute spinules, which are somewhat 

 divergent and are webbed together for about half their length ; 

 they meet or interlock across the furrow, leaving rounded or ovate 

 open spaces between them for the passage of the large and tapered 

 ambulacral feet. These spinules become very small and slender dis- 

 tally, but still meet across the furrow. On the outer and lateral 

 margins of the plates there is also a series of divergent, webbed, 

 fasciolated spinules like those of the actinal plates. 



The jaws are oblong and very prominent on the actinal side ; each 

 half has an actinal sutural row of very small spinules, and some 

 additional ones on the surface. The furrow-series contains about 

 ten spinules, increasing in length toward the apex of the jaw, where 

 'there are two much larger and longer, acute oral spines. 



The madreporic plate is rather large, with fine gyri. The dorsal 

 nephridial pore is situated in the center of a low elevation composed 

 of very small, round paxilla?. 



Taken by the Albatross at station 2401, in the Gulf of Mexico, in 

 142 fathoms. (No. 18,428.) 



Family BENTHOPECTINIDiE Ver., nov. 

 Benthopectinmce Ver., Proc. Nat. Mus., xvii, p. 245, 1894. 



Benthopecten spinosus Verrill. 



Benthopecten spinosus Verrill, Amer. Joiirnal Sci., vol. xxviii, p. 218, 1884; 

 Explorations made by the Albatross in 1883, in Annual Eeport, U. S. Comm. 

 of Fish and Fisheries, pp. 519 [47], 543 [41], 1885. Proc. Nat. Mus., vol. 

 xvii, p. 245, 1894. Amer. Journ. Sci., xlix, p. 129, 1895. 



Pararchaster semisquamahis var. occiclentalis Sladen, Voyage of the Challen- 

 ger, vol. XXX, p. 10, 1889. 



Pararchaser armatus Sladen, op. cit., p. 19, pi. 1, figs. 5, 6; pi. 4, figs. 5, 6, 

 1889. 



Plate XXX. Figures 7, 7a. 



This species was taken north of Cape Hatteras, at 62 stations, 

 between N. lat. 42° 47' and 85° 10', in 721 to 2021 fathoms, by the 

 U. S. Fish Commission. Most common in 1200 to 1600 fathoms. 



It was also taken in the Gulf of Mexico, station 2380 and station 

 2381, in 1430 and 1330 fathoms, and off Jamaica, station 2127, 1639 

 fathoms. 



