PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 505 



cally, face obliquely inward and forward, and are black or brownish 

 black. The peduncle of the antenna and its scale are nearly like those 

 of A. microphthabna. 



The oral api^endages are very nearly as in A. Agassizii. The oppos- 

 ing edges of the ventral processes of the mandibles are a little narrower, 

 almost exactly alike on the two sides, armed with about seven teeth 

 each, and without the small anterior teeth seen in A. AgassizU. The 

 first maxillse show no differences. The divisions of the distal segment 

 of the protognath of the second maxilla are very slightly broader than 

 in A. AgassizU, the endognath and the anterior lobe of the scaphognath 

 are both considerably longer and the posterior lobe of the scaphognath 

 slightly narrower. The exopod of the maxilliped does not reach be- 

 yond the endopod and the tip is broader and more truncated than in 

 A. AgassizU. The gnathopods do not differ essentially from those of 

 A. AgassizU. 



The peraBopods are very similar to those of A. AgassizU, but are all 

 considerably longer and more slender ; the first reach to the middle of 

 the antenna! scale, the fourth to considerably by its tip, and the fifth 

 to about the same i)oint as the first. 



The pleon is smaller relatively to the cephalo-perteon than in A. Agas- 

 sizU and the third somite very differently armed. The first and second 

 somites are rounded above, but the third is strongly compressed dor- 

 sally into a very high and sharp carina which projects in a great later- 

 ally compressed tooth high at base, tapered to an acute point and over- 

 hanging the fourth somite and ])art of the fifth. The fourth, fifth, and 

 sixth somites are compressed and armed with a shari) carina which pro- 

 jects posteriorly in a conspicuous tooth on the fourth, and in a similar 

 but much smaller tooth on the fifth and sixth. The pleura are similar 

 to those of A. AgassizU, but relatively less deep, the second is consid- 

 erably broader, and the third, fourth, and fifth more produced and more 

 evenly rounded posteriorly. 



The telson i?* very long and slender, only very obscurely sulcated 

 above, aruied with approximately five pairs of minute doi'sal aculei and 

 tipped with three slender spines between a pair of much larger lateral 

 ones with a small subterminal spine near the base of each. 



The uropods and pleopods are nearly as in A. AgassizU. 



Measurementa in miUimeters. 



station 2105, 



Sox. 



Length from tip of rostrum to tip of telson . 



Length of carapax inclading rostrum 



Length of rostrum 



Height of carapax 



Length of eye-stalk and eye 



Greatest diameter of eye 



Length of antennal scale 



Breadth of autennal scale 



Length of second gnathopod 



2099. 



65 

 23.0 

 5.1 

 10.6 



77 



26.0 



6.9 



11.7 



2.8 : 3.1 



1.5 L8 



10.7 I 12.1 



3.1 3.& 



21 



