93 64 Proceedings oj the Royal Irish Academy. 



Pachylaelaps littoralis nov. sp. (PI. V, fig. lla-d.) 



On the sea-coast at Mulranny there occurred a male Pachylaelaps, which 

 is apparently unrecorded, The species is remarkable on account of the 

 broad, dagger-like process of the chelicerae, the structure of the epistome, and 

 the processes of the second pair of legs. 



Male (fig. 11a). — Length 819^, breadth 410/*. Colour yellow, with black 

 patches showing through the dorsum. Body strongly produced in front, 

 shoulders sufficiently pronounced, sides slightly emarginate, width across 

 posterior third equal to that of the shoulders, end of the body evenly 

 rounded. Dorsal surface smooth, with four rows of rather stout bristles, 

 including one marginal, upturned, row. There are two pairs of frontal 

 bristles. Ventral surface protected by the usual large bluntly pointed 

 shield, leaving a free marginal area, which is wider than in P. pectinifer. The 

 genital foramen is small and circular ; two minute inguinal plates are fused 

 in the margin of the ventral shield. Peritreme undulate with a rather large 

 circular stigma. 



The epistome (fig. lie) ends in a rather broad process, the apex of which 

 is concave, with about eight teeth, which are distinctly branched at their 

 extremities, somewhat resembling in this respect P.furcifer Oudemans(lO). 

 On the ventral plate there are four pairs of bristles, three of which are 

 placed close to the maxillary lobes. Movable finger of the chelicerae 

 (fig. lid) with two strong teeth, under surface raised, and immediately in 

 front of the prominence there is articulated a broad, dagger-like process, 

 which is distinctly sinuate at the base. Apex of fixed chela bidentate. Palps 

 of the usual type, fourth segment not armed. The tritosternum is weakly 

 developed, base long and narrow, terminal filaments with strong widely 

 separated pectinations (fig. lid). 



Legs comparatively long, the respective lengths are about 793,u, 563/t, 

 486/i, and 665^, second pair (fig. lib), thick; femur armed with a stout 

 conical spur, which is weakly serrated in front, at its base is a bristle-bearing 

 papilla ; patella with a much smaller bluntly pointed tooth, and the tibia is 

 unarmed. The tarsus carries the usual two terminal spurs, which are rather 

 long and slender in the present species. Ambulacra wide, upper membranes 

 consisting of a three-lobed central piece, and a pointed lateral lobe on 

 each side. 



Locality. — The male of this species occurred under stones about four or 

 five feet below high-tide mark on the shore of Bellacragher Bay, near 

 Mulranny, in the month of September. 



