100 BULLETIN OF THE 



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

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

 smaller than the ])air next in front of them. 



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

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

 7.0° 22' 50", 1632 fathoms. The other specimens are from the collections 

 made by the U. S. Fish Commission off ]\Iartha's Vineyard : Stations 893 and 

 952, 372 and 388 fathoms. 



Two specimens give the following measurements : — 



Station 



Sex , 



Length from tip of rostrum to tip of telson 



" of carapax along dorsal line ... 



" 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 sonnte of abdomen .... 



" telson . ...... 



" inner lamella of uropod .... 



" outer " " ... 



This is the species which I have referred to as " Sergestes sp." in Proc. 

 National Mus., Washington, II L p. 445, 1881. 



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. robustus, 

 the po.sterior pleurobranchia of the twelfth (antepenultimate) somite is replaced 

 1)\- a simple lamella like that upon the somite next in front, and the two 

 branchiffi of the penultimate somite are very small, as in 5^. ardicus. The 

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

 aj)pearance, but the rostrum is much smaller and apparently oljtuse, and the 

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

 females. 



