MARINE ISOPODA OF NEW ENGLAND, ETC. 331 



half the width of the preceding segments, bearing near the anterior dor- 

 sal margin two small conical tubercles; pleon slightly longer than the 

 three preceding segments together, but not narrower, forming somewhat 

 more than one-fourth the length of the body, elongate-suboval, the breadth 

 scarcely equaling half the length, with a median, rounded, dorsal crest, 

 but little elevated, and bearing in front of this near the anterior margin 

 a small conical tubercle. 



Propodus shorter than the carpus in the first pair of legs, equal to it 

 in length in the second pair, which in the males (pi. II, fig. 11 e) have 

 the carpus thickened, and armed, on the inferior margin, with stronger 

 spines than in the females ; third and fourth pairs of legs about thrice the 

 lengtn of the body, with the three basal segments, basis, ischium, and 

 merus, very short and robust ; the last three very much elongated and 

 filiform ; the propodus longer than the carpus, both armed with many 

 short spinules arranged longitudinally ; dactylus about one-fifth as long 

 as the propodus, slightly curved, naked, very minutely serrulate along 

 the convex margin. Last three legs (pi. II, fig. 11 f) with the carpus 

 and propodus elongate-subelliptic, both segments strongly cUiated, the 

 propodus a little shorter than the cari)us. 



Abdominal operculum in the female (pi. II, fig. 11 g) with a longitu- 

 dinal, elevated, acute median crest, flattened medially in the males. 

 Uropods slightly more than one-third the length of the pleon, composed 

 of two subequal segments. Lamiujs of the incubatory pouch in the 

 females attached to the anterior four thoracic segments ; the three poste- 

 rior pairs large ; the third and fourth suborbicular ; the second elongate j 

 the fii'st much smaller, bifid at the apex. 



Length S-IO'"™: antennre 40-50""»; third and fourth pairs of legs 24- 

 3Qmm Color, light yellowish, or grayish, in alcohol ; lighter below. 



The specimens that I have had an opportunity of examining were all 

 more or less imperfect, and I have therefore, in botli the generic and 

 specific descriptions given above, made free use of the admirable and 

 exhaustive description of this genus and species by M. Sars,* and the 

 figures of the species on plate II were copied from the same author, 

 having been drawn by his not less distinguished son, G. O. Sars. 



This species hke its allies is an inhabitant of deep water on muddy 

 bottoms. Three specimens, the only ones that I have personally ex- 

 amined, were taken by the Fish Commission in the Bay of Fundy ! be- 

 tween Head Harbor and the Wolves, in GO fathoms muddy bottom, 

 August IG, 1872. It has been dredged by Mr. Whiteaves in the Gulf 

 of St. Lawrence in 125 to 220 fathoms; by the Valorous Exi)edition 

 in Baffin Bay in 100 fathoms (Norman) ; in 25 to 50 fathoms off Cape 

 JS'apoleon, Grinnell Land, by the Arctic Expedition (Miers) ; between 

 Norway and Iceland in from 220 to 417 fathoms; Christiania fiord, 

 200 to 230 fathoms (G. O. Sars) ; Christiania Sound 50 to GO fathoms, 



* Bidrag til Kundskab om Christiania-:Qorden8 .Fauna, 1868, pp. 70-95, pis. vi-vii, 

 (Nyt Magazin. ) 



