»10 Mr. E. W. Sexton on 



LX. — A neio Amph'pod Species, Tryphosites alleni. By 

 E. VV. Sexton, Marine Biological Laboratory, Plymouth. 



[Plate XIV.] 



Two specimens of the species described below were taken by 

 Dr. Allen during the cruise of the ' Huxley' in the north of 

 the Bay of Biscay, August 1906, trawled in 246 fathoms, 

 48° 7' N., 8° 13' W. 



Fam. Lysianassidae. 



Genus TiiYrHOSlTES, G. 0. Sars. 



Tryphosites alleni^ sp. n. (PL XIV.) 



Two specimens, ovigerous females, measuring 10 mm. from 

 the tip of the rostrum to the tip of the telson. 



Besides these two specimens I have been able, through 

 Mr. Tattersall's kindness, to examine some fourteen others, 

 taken, together with the type species, T. longipes, by the 

 ' Helga ' on the west of Ireland, in 200 fatiioms. Tliey w^ere 

 of all sizes, measuring from 2*5 mm. to 10 mm. in length ; 

 the four largest were males. 



With regard to the distribution of the two species, Mr. 

 Tattersall has informed me that " T. longipes is alone found 

 in shallow water. The other form is alone found in very 

 deep water, and the two forms together in intermediate 

 depths." 



Description. 



In general aspect much resembling the type species, 

 T. longipes'^, the principal distinguishing ciiaracters being 

 found in the hand of gnatliopod 2, the sliape of side-plate 4, 

 llie epiniera of pleon-segmeiit 3, and the telson. 



Head longer than the tirst pera'on-segment, but not equal 

 to the tirst two in length; lateral corners niucli produced and 

 acute. 



Eyes large, a long oval, pigment faded. 



tSide-plates as in the type species with the exception of 

 side-plate 4 ; in this (fig. 1) the projecting portion of the 

 lower hind margin is rounded, in longipes it is truncate and 

 angular. 



* A full description and figures will be found in Prof. Sars's ' Crustacea 

 of Norway, ' vol. i. p. 81, pi. xxyiii. fig. 3, and pi. xxix, fig. 1. 



