ArysicUu //'om the ^^est Coast of Irelanl. 113 



formed, arc bettor developed and more numerous than in 

 Daclylenjthropa, rcacliinj? to tlic surface of the eye and 

 probably diri*ctly functional as organs of sight; outer distal 

 corner rounded and not produced into a digitiform process ; 

 a short process always present on the inner and upper surface. 



Type species, Ductylamhhjups llodysoiii, II. & T. 



The type and the two new species described below appear 

 to form a natural group chicHy distinguished from the 

 genus Dactylenjihrops by the above points, and in the present 

 state of our knowledge of the group this generic division 

 may well be allowed to stand. 



Dactylcrytlirops arcnata, Illig, should be referred to this 

 gvuuis, and is, in fact, synonymous with the type species, 

 D. Hod (J so III. 



Dactylamblyops thaumatops, sp. n. 



Cai-apare covering all the thoracic segments except the 

 la-t ; produced in front into a short, broadly rounded, 

 obtuse rostrum, which extends to the distal end of the first 

 joint of the antcnnular peduncle and partially covers the 

 eye-stalks ; evenly rounded at the antero-lateral corners and 

 emarginate behind ; cervical sulcus well marked. 



Pleon longer than the carapace ; the first segment a little 

 longer than the second, which is subequal to the third, 

 fourth, and fifth; sixth segment twice as long as the fifth. 



Eyes small, cxtcniling forwards to the distal end of the 

 second joint of the antennular peduncle ; pyriform in shape, 

 with distinct eye-stalks ; each eye with a short digitiform 

 l)rocess on the inner and upper face; a broad membranous 

 ledge projecting at right angles to the surface of the cornea 

 starts at the outer lateral part of the eye-stalk and runs 

 cquatorially round the outer ])art of the eye, terminating 

 just ventral to the digitiform process and dividing the cornea 

 into a dorsal and ventral portion ; the ledge is broadest 

 about the centre of the cornea and narrows off at either end ; 

 visual elements imperfectly developed, numerous, reaching to 

 the surface of the eye; pigment pale pur})lish pink. 



Antennular peduncle about twice as long as the eve and 

 three ([uarters of the length of the antcnnal scale; third 

 joint slightly longer than the first; second j(jint small. 



Antennal peduncle about half as long as the scale ; the 

 three joints roughly subequal in length. 



Antcnnal scale about one third as long again as the 

 antennular ])ed uncle and twice as long as the antcnnal ; 

 about four times as long as broad ; outer margin entire and 



Ann. iL Maj. A'. Llibt. .Scr. 7. VuL xix. 8 



