100 



BULLETIN OF THE 



is nearly as large as the anterior, -which is the largest of the series, and the 

 branchiae of the penultimate segment are very nearly alike, and not very much 

 smaller than the pair next in front of them. 



I have seen only four specimens, all males, and but one of these is in the 

 " Blake " collection ; this one from Station 328,) N. Lat. 34° 28' 25", W. Long. 

 75° 22' 50", 1632 fathoms. ( The other specimens are from the collections 

 made by the U. S. Fish Commission off Martha's Vineyard -. Stations 893 and > 

 952,) 372 and 388 fathoms. 



Two specimens give the following measurements : — 



Station . 893 



Sex g 



Length from tip of rostrum to tip of telson . . . 58.0 mm. 



" of carapax along dorsal line . . . 17.8 



' 



" of rostrum . 

 Height of carapax anteriorly 



" " posteriorly . 



Breadth of carapax 

 Length of eyestalk and eye 

 Diameter of eye .... 

 Length of antennal scale 

 Breadth of antennal scale 

 Length of sixth somite of abdomen 



" telson .... 



" inner lamella of uropod 



" outer " " 



1.2 

 4.0 

 8.5 

 5.6 

 3.5 

 1.7 

 9.0 

 2.9 

 9.0 

 7.5 

 8.0 

 110 



This is the species which I have referred to as " Sergestes 

 National Mus., "Washington, III. p. 445, 1881. 



328 



$ 

 65.0 mm. 

 19.5 



1.3 



4.5 



9.5 



6.3 



3.9 



1.9 



9.2 



1.3 

 10.0 



8.0 



8.3 

 12.0 



)." in Proc. 



Sergestes, sp. indet. . 



There are specimens of a third species of Sergestes from Station 328, N. Lat. 

 34° 28' 25", W. Long. 75° 22' 55", 1632 fathoms, and fragments of apparently 

 the same species from Station 325, N. Lat. 33° 35' 20", W. Long. 76°, 647 

 fathoms. These specimens are all in bad condition and want a large part of 

 the appendages, but they are interesting on account of the modification of the 

 branchial formula. The branchiae are all much smaller than in S. robushis, 

 the posterior pleurobranchia of the twelfth (antepenultimate) somite is replaced 

 by a simple lamella like that upon the somite next in front, and the two 

 branchiEe of the penultimate somite are very small, as in S. arcticus. The 

 species is apparently even larger than S. robustus, and much like it in general 

 appearance, but the rostrum is much smaller and apparently obtuse, and the 

 eyes are very small, scarcely larger than eyestalks. The specimens are all 

 females. 



