702 THE VOYAGE OF H.M.S. CHALLENGEK. 



hand with some small spines on the front margin, this joint and the finger very similar 

 to these in the two preceding pairs. 



Fourth Perwopods.- — Side-plates small, somewhat produced downwards behind. First 

 joint a broad oval, the lower lobe behind overlapping the second joint, the front 

 margin with strong spines except at the upper part, the hinder margin not strongly 

 serrate ; the third joint broad, decurrent, spined on both margins ; the rest of the liml) 



Fifth Perwoioods. — The first joint broader and longer than that of the preceding pair, 

 front margin spined, hinder serrate, with its broadly rounded lower lobe produced beyond 

 the second joint ; third joint narrower than in the two preceding pairs ; in other respects 

 the joints similar to those of the third j^erseopods. 



Pleopods. — There are some slender spines on the margins of the peduncles ; the 

 coupling spines are slender, with two lateral retroverted teeth and the apices acute, little 

 bent ; there are two cleft spines in the second pair, only one in the third pair ; the arms 

 of the cleft are nearly equal, apparently neither of them having a spoon-shaped 

 termination; the joints of the rami number from eight to eleven. 



Uropods.- — The ]^)eduncles of the first pair longer than the rami ; the rami stiliform, 

 with few marginal spines, the outer ramus longer than the inner ; peduncles of the second 

 pair about equal to the rami, inner ramus longer than the outer, projecting beyond the 

 rami of the third pair ; peduncles of the third pair shorter than the rami, which are 

 subequal, not very broadly lanceolate, with three marginal spines on the outer side of 

 the outer ramus. 



Telson not reaching nearly to the end of the peduncles of the third uropods, 

 longer than broad, cleft scarcely beyond the centre, not dehiscent, with convex sides 

 narrowing distally, the apices rounded. 



Length. — The specimen, in the position figured, measured from the rostrum to the 

 back of third pleon-segment a little over one-fifth of an inch. 



Locality. — Station 161, off Melbourne, April 1, 1874; depth, 33 fathoms; bottom, 

 sand. One specimen. Trawled. 



Remarhs. — The specific name, from /3a6w, deep, and KecjyaXy], a head, refers to the 

 very conspicuous depth of the head in this species. 



Through the kindness of Mr. W. A. Haswell I have had an opportunity of comparing 

 the present species with a specimen of his Amaryllis hrevicornis, which he distinguishes 

 from his Amaryllis macrophthalmus only by the greater shortness of the antennae. The 

 specimen he sent me was a female with young, and there can be in my opinion no doubt 

 that hrevicornis should be entered as a synonym of mcccrophthcdnms. From this the 

 Challenger sjpecies difters, not only in having much less numerously jointed flagella to 

 the antennae, the secondary of the upper having three joints instead of thirteen (in the 



