Boone, Crustacea, Cruises of "Eagle" and " Ara," 1921-28 135 



Genus : SYSTELLASPIS Spence Bate. 

 Systellaspis debOls (A. Milne Edwards). 



Plate 46. 



Type: The type was collected in 500 fathoms in the Bahama 

 Channel, and is deposited in the Paris Museum. 



Distribution: Rather widely distributed in the bathypelagic At- 

 lantic; also once recorded from the Pacific, in the vicinity of Kauai 

 Island, Hawaiian Islands, and a subspecies, variety indica deMan, 

 taken by the " Siboga" in the Halmaheira Sea at 798 meters. The 

 Atlantic records include four specimens taken between New York and 

 the West Indies, one record south of Iceland; numerous specimens 

 taken by the "Thor" in the northeast Atlantic and by the "Helga" 

 in the Atlantic through the area ranging from the Faroes to the Bay 

 of Biscay, also in the mouth of the English Channel, and off the coasts 

 of Brittany, also west of the Cape Verde Islands and in the South 

 Atlantic, at Lat. 35° 39' S., Long. 8° 16' W. 



Material examined: Two females dredged in 150 fathoms, seven 

 miles off Alligator Reef, March 20, 1926, by the ''Ara." 



Technical description: Female. Rostrum broken off about mid- 

 way its length, body angulated behind the third abdominal segment. 

 Carapace, from the orbital angle to posterior margin 9.5 mm. long; 

 abdomen, including telson, about 33 mm. long. Rostrum (broken) 

 slightly arched above the orbit, thence deflected briefly and with the 

 distal portion apparently directed upward. 



The rostral carina is continuous onto the carapace for about half 

 the length of the latter, and with a dorsal median gastric spine near 

 its posterior end. The broken rostrum bears three spines on its upper 

 surface, one above the orbital angle, the remaining two, anterior to 

 this and subequally spaced. The lower margin has two spines, the 

 hinder of which is about in line with the most anteriar of the spines 

 on the upper margin. The carapace is smooth with a sharp spine at 

 the upper antennal angle. The abdomen has the first segment shorter 

 than the second ; the third segment, produced, one and one-half times 

 as long in the median line as the second segment ; the fourth segment 

 slightly longer than the second segment; the fifth segment about 

 three-fourths as long as the fourth ; the sixth segment is about twice 

 as long as the fifth; the telson is about as long as the sixth segment, 

 tapering with a brief, truncated apex which is armed with a pair of 

 long, acute, articulated spines, and the dorsal surface is armed with 



