PAET III 



THE NATURAL ENEIVIIES ANL> PARASITES OF 



THE HOUSE-FLY 



CHAPTER X 



ARACHNIDS AND MYRIAPODS 

 ClIERXES XODOSUS SCHRANK. 



There are frequently found attached to the legs of the house- 

 fly small scorpion or lobster-like creatures which are Arachnids, 

 belonging to the order Pseudo-scorpionidea ; the term " chelifers " 

 is also applied to them on account of the large pair of chelate 

 appendages which they bear. The species which is usually found 

 attached to M. domestica is Ghernes nodosus Schrank (fig. (iO). 

 It is very widely distributed, and my observations agree with 

 those of Pickard-Cambridge (1892), who has described the group. 



The species is 2*5 mm. in length and Pickard-Cambridge's 

 description of it is as follows : 



" Cephalothorax and palpi yellowish red-brown, the former 

 rather duller than the latter. Abdominal segments yellowish- 

 brown ; legs paler. The caput and first segment of the thorax 

 are of equal width (from back to front) ; the second segment of 

 the thorax is very narrow. The surface oi' the cephalothorax and 

 abdominal segments is very finely shagreened, the latter granulose 

 on the sides. The hairs on this part as well as on the palpi and 

 abdomen are simple, but obtuse. The palpi are rather sharp and 

 strong. The axillary joint is considerably and somewhat sub- 

 conically protuberant above as well as protuberant near its base 

 underneath. The humeral joint at its widest part, behind, is 



