40 Proceedings of the Royal Irish Academy. 



anterior margin of head. (Britannic species always with groove marking off 

 head, and generally with another limiting the two thoracic somites.) 



Species numerous ; formerly divided into Atcmnv^s, Cherncs, and Chelifcr 

 S.S., artificial genera now usually abandoned ; With (66, 82) has recently shown, 

 however, that four natural divisions are distinguishable — (1) group of 

 G. IHrmanicus, (2) group of G. cimicoides, (3) group of 0. cancroides, (4) group 

 of C. suhruher ; and these groups which are at least sub-genera are here 

 adopted as (1) Atemnus, (2) Chernes, (3) Clielifcr s.s., redefined ; and (4) 

 Withius, sub-gen. nov. 



1. Fingers of palps with accessory teeth . . . Ghernes. 

 Fingers of palps without accessory teeth .... 2 



2. Legs I. with articulation between trochantin and femur wide, 



oblique Ghelifer s.s. 



3. Legs I. with articulation between trochantin and femur rather 



narrow, almost perpendicular . . . . Within^} 



L Chernes Menge 1855 (20).= 



Legs I. with articulation between trochantin and femur wide, oblique; 

 fingers of palps with accessory teeth ; $ without coxal sac, genital-area 

 with plate 11. not longer, usually shorter than plate I., without ram's-horn 

 organs. Eyes (in Britannic species). 



(Britannic species 9 : abdomen with tergite T. incompletely or more often 

 completely divided, the rest divided, except XL which is incompletely 

 divided or more often entire ; main tergites generally with four bristles in 

 front of the posterior marginal row; palps more or less robust, femur usually 

 increasing abruptly fioni its stalk and attaining its full breadth near base, 

 tibia usually with marked auterio-proximal convexity, hand sometimes both 

 broad and obliquely high, posterior margin of fingers with a series of accessory 

 teeth, anterior margin with a series or with an isolated tooth ; S with genital- 

 area and secondary characters moderately conspicuous, and with coxae IV. 

 straight or nearly so posteriorly, moderately or but little modified.) 



1. Body polished ; tibia IV. with tactile hair .... 2 

 Body unpolished ; tibia IV. without tactile hair ... 4 



2. Trochanter of palps with upper protuberance broad, showing on 



posterior margin Ghyzcri. 



Trochanter of palps with upper protuberance narrower, not 

 showing on posterior margin 3 



' Atemnus is unrepresented in our fauna. 



- Ghelanops Gervais 1849 (18) has sometimes been used in place of Chernes ; but its type is not 

 knoWM to pertain to the present sub-genus. 



