164 THE VOYAGE OF H.M.S. CHALLENGER. 



three divisions, of which the anterior is serrate with eight teeth, the middle with five, and 

 the posterior with eighteen or twenty teeth. The armature may be tabulated as — 



Marginal, ....... 8 — 5 — 18 



Dorsal ridge, ...... 111211—2111 



The pleon is carinated, and furnished on each somite with an anteriorly-directed 

 tooth, of which those on the second, third, fourth, and fifth somites are the largest. 



The first pair of pereiopoda is long and slender, smooth on the outer side of the 

 meros, excepting the distal angle, where there are two small teeth ; the inner margin is 

 furnished with a number of small denticles ; the carpos is slender, smooth on the inner 

 side, but fringed with small denticles chiefly at the propodal extremity on the outer ; 

 the propodos is serrate on the outer margin, and armed with a strong, sharp, straight 

 tooth on the inner surface of the pollex, one-third distant from the apex. 



The succeeding pairs of pereiopoda are all chelate, but much shorter than the first. 



Habitat— Station 13, March 4, 1873 ; lat. 21° 38' N., long. 44° 39' W.; depth, 1900 

 fathoms ; bottom, Globigerina ooze ; bottom temperature, 36° - 8. Length (female) 

 75 mm. (3 in.). 



Station 133, October 11, 1873; lat, 35° 41' S., long. 20° 55' W.; depth, 1900 

 fathoms; bottom, Globigerina ooze ; bottom temperature, 35°*4. Length (female) 75 mm. 

 (3 in.). 



Station 298, November 17, 1875; lat. 34° 7' S., long. 73° 56' W.; depth, 2225 

 fathoms; bottom, blue mud; bottom temperature, 35°"6. Length (female with ova) 

 75 mm. (3 in.). 



Station 300, December 17, 1875; lat. 33° 42' S., long. 78° 18' W.; between 

 Valparaiso and the Gulf of Penas ; depth, 1375 fathoms; bottom, Globigerina ooze; 

 bottom temperature, 35°"5. Length (male), 110 mm. (4 - 5 in.). 



In August 1881 Prof. Giglioli 1 recorded a specimen of this species from the west 

 coast of Sardinia, at a depth of 3000 metres. 



The dorsal surface of the carapace is depressed, nearly flat, and is minutely granulated ; 

 from the apex of each granule springs a small, stiff, slightly curved hair. Lines of 

 elevation armed with small teeth traverse the post-lateral median line, and define the 

 regions of the internal organs. The ridge which traverses the post -lateral dorsal surface 

 of the pereion, and marks the internal boundary of the branchial chamber, is longi- 

 tudinally armed with a number of small teeth, all of which are directed forwards. The 

 ridge corresponding with the cervical fossa is smooth, and free from teeth ; so also is its 

 anterior lateral branch, while that which runs from the inner angle of the orbit posteriorly 

 in a flexuous line commences in a small but sharp and strong tooth. The frontal and 



1 Nature, vol. xxiv. p. 358, 1881 ; Ann. d. Sci. Nat, ser. 6, vol. xiii. p. 5. 



