98 BULLETIN OF THE 



A single specimen of this species, the only one as yet known, was taken at 

 Station 305, Lat. 32° 18' 20" N., Long. 78° 43' W., from a depth of 252 

 fathoms. 



Rocinela Americana Schiodte & Meinert. 



Plate III. Figs. 3, 3 a, 4. Plate IV. Figs. 2, 2 a. 



Rocinela Americana Schiodte & Meinert, Naturhist. Tidssk., R. III., B. XII., 

 p. 394, PL X. (Cym. IV.) figs. lG-18. 1879. 



Two specimens of this species were obtained at Station 320, Lat. 32° 33' 15" 

 N., Long. 77° 30' 10" W., from a depth of 257 fathoms, and a considerable 

 number of other specimens obtained at various localities by the U. S. Fish 

 Commission enable me to add somewhat to Schiodte and Meinert's description 

 of the species, which was drawni from a single female specimen. A comparison 

 of their type, from Trenton,"^ Maine, now preserved in the Museum of Com- 

 parative Zoology at Cambridge, and kindly loaned for the purpose by Pro- 

 fessor Agassiz, shows no differences that can be regarded as specific. 



The body is oval, with the length more than twice the breadth, and nearly 

 all of our si^ecimens are proportionally broader than the type, although none of 

 them are quite as large. 



Head subtriangular, rounded behind, acutish or slightly produced in front, 

 more distinctly produced and somewhat angulated in front in the males (PI. 

 III. Fig. 4). Eyes rather large, separated by about one quarter the diameter 

 of the head, rounded behind, more or less angulated at the point of nearest 

 approach, where, in the males, a distinct angle of a hexagon is seen at the 

 meeting of two rows of nine and six ocelli along the inner margin of the eye, 

 one ocellus at the angle being common to both rows. 



The antennulae, when reflexed, only slightly surpass the head, and the flagel- 

 lum is composed of five or six segments, of which the first is not much elon- 

 gated and the last nearly attains the end of the antennal peduncle. The 

 antennre nearly attain the hinder margin of the second thoracic segment ; the 

 first and second segments are very short and concealed by the projecting front ; 

 the flagellum is as long as the peduncle, and composed of about fourteen seg- 

 ments. 



The first thoracic segment is slightly excavated for the ocular lobes of the 

 head; epimera of second and third segments subquadrate, oblique but not acute 

 behind, marked with an impressed line near the lower margin ; remaining four 

 epimera acute and moderately produced ; last epimeroii usually surpassing the 

 first segment of the pleon, although in some of the larger females, as in the type 

 specimen, it fails to do so. 



Prehensile legs (PI. IV. Fig. 2) armed with three acute spines on the palmar 

 margin of the propodus, and three obtuse spines on the same margin of the 



* Trenton is incorrectly printed "Ireston" in Schiodte and Meinert's paper. 



