498 R. T. LEWIS ON AN UNDESCRIBED SPECIES OF CHELIFER. 



me to take the matter up, oifering to place the museum examples 

 at my disposal for the purpose, my own having been mounted 

 unset, and having the feet curled up underneath and embedded 

 in gum. I therefore arranged to spend an afternoon in the 

 Arachnida room, and as an exhaustive search in the literature 

 on the subject in the Museum library throws no further light on 

 the question, I have completed my description, and have great 

 pleasure in adding this, together with the drawings now^ exhibited, 

 to the very valuable compilation of Dr. Cooke in our own reference 

 library. 



This Chelifer is of a bright red colour. Body ovate, much 

 narrowed in front and semi-circular behind. Length, -125 inch; 

 greatest breadth, '105 inch. Abdomen divided into twelve 

 segments, of which eleven are sculptured on the dorsal side 

 with circular depressions, each having a raised central spot ; 

 a longitudinal median depression becomes apparent at the 

 fourth segment, and is increasingly well marked thence to the 

 posterior extremity. The first three joints of the palpi are 

 thickly studded with sub-conical elevations or tubercles, each 

 bearing a short stiff hair on the anterior side a little below the 

 apex. The fourth joint comprises the powerful forceps, the upper 

 and immovable jaw of which is hollowed near the incurved tip, 

 whilst the lower jaw is of equal length but somewhat less curved ; 

 both are fringed with stiff hairs, and are admirably adapted for 

 firmly holding an insect by its leg without risk of cutting it 

 through. The anterior portion of the cephalo-thorax, im- 

 mediately above the eyes, is furnished with a row of six or 

 seven spiny hairs. Eyes two. Palpi four- jointed : first, 

 •02 inch long x '0175 inch at greatest breadth ; second, 

 •05 inch long X "02 inch at greatest breadth ; third, '04 inch 

 long X '0225 inch at greatest breadth, — these three studded with 

 subcorneal tubercles ; fourth, forceps "06 inch long x '0275 inch 

 at widest part, without tubercles, but covered with fine flexible 

 hairs. Legs : first joint shortest ; second (femur) longest ; third 

 (tibia) and fourth (tarsus) of equal length. Glaws two. Margin 

 of abdomen of female crenulated by one semicircular process at 

 each segment except the last. Margin of abdomen in male, 

 first three segments and the last same as in the female, fourth 

 to eleventh segments inclusive terminating in a strong recurved 

 hook-like process. 



It is proposed to name this species Chelifer scidjyturatus. 



Explanation of Plate 25. 



Fig. L Chelifer sculpturatus n. sp., ?, dorsal aspect x 15. 

 9 j^ V 1 "5 



55 -•• )> :j >) O J 55 55 /N J.I/. 



„ 3. „ ,, „ Forceps, lateral aspect x 15. 



Journ. Quekett Microscopical Club, Ser. 2, Vol. VIII., No. 53, November 1903. 



