ACARI 609 



Département de VArdèche [France). — Baoumo delaCampana, 

 commune de Saint-Martin-d'Ardèche, canton du Bourg-Saint- 

 Andéol, 31 st August 1909 ; N" 285, — one spécimen. 



Distribution : of main form : Europe, Egypt 



The variety described below is of spécial interest, since it 

 offers us an opportunity for studying, at least in one cavernico- 

 lous species, the way in which this peculiar mode of life lias 

 modified its shape. 



Length : 900 to 1260 y.. Width : 250-300 a. 



The colour is white ; but it may be that the animais are deco- 

 lorated by the alcohol. The cuticle isfinely villous. The gênerai 

 shape is thesameas in the main form, as is also the relative 

 length of the cephalotorax, and the abdomen. 



The c e p h a 1 o t h o r a X has at the front edge , in the middle , the 

 so-called « pseudocapitulum », which is rounded, semispherical, 

 and bears a pair of fine sensorial hairs which attain a 

 length three eighths that of the mandibles. It bears 3 pairs 

 of long hairs, placed as foUows : one pair, pointing straight 

 outwards, at the posterior angles ; one pair a little in front of, 

 and inwards from, thèse ; and one pair nearer the middle, and 

 somewhat farther back, as far from each other as from the 

 second pair. 



Gnathosoma. Mandibles slightly longer than the céphalo- 

 thorax (fig. 142), and three times as long as their greatest 

 width, which is in the middle of the trunk. They are a little 

 slenderer and straighter than in the main form. They also 

 differ in so far as the ventral edge of the upper jaw forms an 

 even curve, other wise they agrée well. Thus the anterior hair 

 is placed submarginally, and externally, and projects beyond 

 the c h e 1 a : below this there is as mail longitudinal ridge. The pos- 

 terior one is marginal and small ; not projecting as far as the 

 place of insertion of the anterior one. Lower jaw with smooth 

 upper edge, and only slightly widened condylus. 



Maxillary palpi (fig. 143). The fourth joint is longer than 

 the second one (4 : 3), whereasin the main form, according to 



