OF THE ' SOUTHEEN CROSS ' EXPEDITION. 59 



Head about as long as the first two segments ; rostrum about 

 one-fourth the length of the 1st joiut of the upper antennae ; 

 lateral angle as in A. carinatus (Fabr.). Eyes rather large, 

 oval, dark. 



Mouth-organs as in A. carinatus (Fabr.) except the mandibular 

 palp, the 3rd joint of which is rather shorter than the 2nd. 



Upper antenuge about one-third longer and thicker than the 

 lower, about two-thirds the length of the body; 1st joint of 

 flagellum longer than the 2nd and 3rd, the 2nd more than twice 

 as long as the 3rd. Magellum about twice as long as the 

 peduncle. Accessory appendage half as long as the 1st joint of 

 the flagellum. 



Lower antennae : the peduncle reaches to the end of the 2nd 

 joint of the upper ; 1st joint one-third the length of the 2ncl, 

 which is rather longer than the 3rd. 



G-nathopods almost alike, the first a trifle the smaller ; tliey 

 closely resemble those of A. carinatios (vide Gr. O. Sars, ' Amphi- 

 poda of Norway,' p. 471, pi. 166), except ia being less setose, 

 especially on the anterior margin of the propodos. Side-plates 

 oblong, narrowing slightly below, with the angles rounded. 



First and second perseopods longer and more slender than in 

 A. carinatus, the 3rd joint very little expanded distally and 

 almost as long as the 5th. 



Third peraeopods with the 1st joint oblong, narrowed below, 

 the margins straight, rather longer than the 3rd joint, which is 

 very slightly expanded distally; 3rd, 4th, and 5th joints subequal. 



Fourth peraeopods similar in form but rather longer than the 

 3rd; 1st joint oblong, the hiud margin slightly concave. All 

 three pairs have five pairs of spines on the anterior margin of 

 the 5th joint. The 5th pair have the 1st joint rather wider, with 

 the hiud margin convex and serrate. 



First and second uropods subequal in extent, the 3rd reaching 

 a little beyond them. The outer rami are shorter than the inner, 

 especially in the 2nd pair ; the peduncles are longer than the 

 rami in the 1st and 2ad and rather shorter in the 3rd, these have 

 a few spines on both margins, but no setae. 



Telson reaching just beyond the end of the peduncles of the 

 3rd uropods, tapering distally, with a narrow cleft about one- 

 third of its length ; the ends of the divisions truncate, with a 

 seta and setule a little before the end of each. 



Length of female with ova 15 mm. 



