Mysidgp /rom the West Coast of Ireland. Ill 



the length of the tclson, apparently withojit spines on its 

 inner mar<;in ; outer, twice the length of the telson. 



Length of a mature female 10 mm., of an immature 

 female 14 mm., and of an immature male 15 mm. 



Localily. Two females and one male from S.R. 3.')2, 92 

 miles S.W. hv W. of Mull Rock, Co. Kerrv, lat. 50^ 22' N., 

 long. 11° 4(y"\V., 800 fath., August 1906, Petersen trawl at 

 750-800 fath. 



This species while ohviously congeneric with D. dadijlops 

 is abundantly distinguished from it by the better developed 

 rostrum, the two processes of the eye, the longer antennal 

 scale, and the greater number of spines arming the margins 

 of the telson. 



Dactylerythrops graciluroy sp. n. 



Carapace covering all the thoracic segments ; broadly and 

 evenly rounded in front, -without any trace of a rostral 

 projection ; antcro-lateral corners rounded ; emarginate on 

 its posterior border. 



rieon a little longer than the carapace ; first secrment a 

 little shorter than the second, which is subequal to tlie third 

 and fourth ; fifth segment slightly longer than the fourth ; 

 sixth segment one and a half times as long as the fifth. 



J- yes very small, almost entirely covered by the carapace ; 

 very tliin and membranous; united at their bases by a 

 membranous integument ; outer distal corners prodiiced into 

 a very acute fairly long flexible process ; a shorter and less 

 acute process on the inner corner ; visual elements very 

 imperfectly developed, confined to a small deeply-seated mass 

 at the base of the outer process ; no pigment observed in 

 preserved specimens. 



Antennnlar peduncle rather short; about half as long as 

 the antennal scale; basal joint flattened and broader than 

 the other two ; second joint small ; third joint the longest, 

 moderately stoutly built, produced vcntrally between the 

 bases of the two tlagelia into a shoi't process armed with 

 about six strong settle; the whole appendage in lateral view 

 appears curiously contorted. 



Antennal peduncle slightly shorter than the antennular 

 peduncle and likewise slightly contorted in lateral view; 

 rather stout; second joint the largest. 



Ante/inal scale almost twice as long as the antennular 

 peduncle; from two and a half to three times as long as 

 l)road ; outer margin entire, terminating in a strong spine, 

 beyond which the apex of the scale is produced for a length 



