134 Proceedings of the Royal Irish Academi/. 



and more strongly clubbed pseudostigmatic organs and the more expanded 

 shoulders. From 0. cx-ilis (Nicolet) and 0. rennsta Berl., liy the strongly 

 narrowed lamellae and the more elongate form of the body. 



Habitat. — Occurs in numbers under dry or slightly damp llakes in the 

 Orange Lichen zone on the rocky shore at Malahide, often in company witli 

 Bhyncholoph^is araiuoides l>erlese. I have also found it under lichens growing 

 on boulders on the seasliore at Howth with such species as Orihata panncliac 

 and Nothrns invcmistus. 



Scutovertex bilineatus Micliacl. (PI. XXII, fig. 18.) 



Under moist limestone llakes in the Orange Lichen /.one at Malahide, in 

 places where there were also black encrusting lichens, February. Tiie adults 

 and nymphs were clustered, round llie edges of the flakes. Ai Ardfry it 

 occurs under stones resting on mud in tiie J'elvelia zmie and upwards to tlje 

 sward above tho Orange Lichen zone, June. Common at Westport under 

 stones on the seashore at a little above high-water mark, July. 



Scutovertex Spoofl Ouiims. \^\'\. XXII, lig. 17 a, b.) 

 1900 Oudemans,39, \>. 112. 1901 S. Liliiuaiics Oudeinans 40, ]). 70. 



Described by Oudemans froni specimens fouml in l'"iid;ind by Dr. A. R. 

 Spoof " in spawn of Lymnaea in sub-saline water " (39). In a later paper he 

 recoi-ds it as synonymous with S. hUineatus Michael (40). At Malahide I 

 liave found both S. bUineatus and S. S/ioofi, which I consider is a distinct 

 si)ecie8. A])art from otlier dilFerenccs, tliey nniy be readily se]mraled by the 

 structvire of llie claws. Michael has accurately described these in the (ase of 

 6'. W/iWff/iM (fig. \i<): "The claws are monodu<-.tyle, but there is a niinuU' 

 projection at each side of the claw, and two long fine hairs sharply hooked at 

 their distal «-nds," v^c. (36). On the other hnnd, the claws, tlioiigli of unequal 

 thicknesses, are undoubtedly tiiree in number in 6'. .S/'oo/i, and are just as we 

 find them in S. scnlptns and other triilactyle species. It would appear 

 likely that the lateral claws are rudimentary in S. hilivcatus, and are repre- 

 sented by the minute projections on each side of the n)iddle claw, as described 

 by Michael. These can be seen distinctly under a high magnitication ; and 

 it may be note<l that the hooked hairs are also present in S. Spoo/i. The 

 latter species also differs from S. hilinc/iinx in the following characters : — Tho 

 cephalothomx (fig. 17a) is larger, and the central finrow is more defined ; the 

 abdomen is more strongly narrowed in front, so that it is less regularly 

 oval than in bilinaUus; it is also leas coarsely punctured and the longitudinal 



