My.skla?/ro»j the West Coast of Ireland. 117 



second, tliiid, ami fourth segments ; sixth one :uul a lialf 

 times as h^ng as the (il'th. 



Eyes strongly recalling those of Ambhjops, rather small, 

 somewhat llattencd and snbqnadrangular in shape, not 

 reaching to the distal end of the first joint of the antcnnular 

 pednncle ; a|i[)arently witliont definite peduncles ; set very 

 close together; visual elements imperfectly developed and 

 without pigment in preserved specimens. 



Antennulur peduncle a little sliorter than the telson, mode- 

 rately stout, third joint equal in length to the basal two 

 comljined ; male appendage well developed and densely 

 hirsute. 



Aiitennal peduncle a little sliorter than the antcnnular, 

 slender, the second joint one and a half times as long as the 

 third. 



Antennal scale equal in length to the telson and a little 

 longer than the antcnnular peduncle ; about four and a half 

 times as long as broad ; shortly lanceolate or oval in shape ; 

 setose all round ; spine on basal joint almost obsolete. 



Mouth-parts and thoracic limbs as described above in the 

 generic definition. The cxopods have the outer corner of the 

 basal joint rounded and tlie flagelliform part composed of 

 twelve joints. 



Pleopods of the male as described for Leptomysis. The 

 fourth pair have the outer ramus longer than the inner; 

 the last three joints are devoid of setse ; the antepenulti- 

 mate joint carries a single long and powerful plumose or 

 barbed spine ; a similar but much shorter spine is found on 

 the penultimate joint, wliilc the terminal joint has two of 

 these long barbed spines. 



Telsun a little longer than the last segment of the plcou 

 and twice as long as broiid at it.s base ; narrowing slightly 

 towards the apex, where its breadth is equal to one third of 

 the total length ; cleft very deep and fairly wide, extending 

 for one third of the total length ; the apical lobe on each 

 side of the cleft bluntly rounded at its tip; cleft serrated, 

 with about thirty spines on each side ; lateral mari^ins armed 

 throughout their entire length witii about forty spines, 

 which increase slightly in length towards the apex, but there 

 is no single outstanding long spine at the apex of each lobe 

 as seen in species of Mynis and Schistomysis. 



Uropods broken in the specimen ; inner one with a row of 

 spines all along its inner ventral margin, thirty-four being 

 counted on that part of the uropod which remained and 

 which extended a little beyond the apex of the telson. 



