394 ARACHNIDA ARANEAE CHAP. 



seldom exceeding 2 mm. in length (the largest 4 mm), living 

 among vegetable debris. Oonops pulcher, the only English repre- 

 sentative of the family, is not rare under stones or in the debris 

 at the bottom of hedges. It is a small brick-red spider, easily 

 recognised by its six comparatively large oval eyes, which are 

 pale-coloured, and occupy the whole of the caput. 



The minute spiders of this family were until recently over- 

 looked by collectors in foreign countries, but now more than a 

 hundred species have been described, belonging to some eighteen 

 genera. Thirteen species inhabit the Mediterranean region, 

 occurring especially on the African side. In several genera there 

 is a " scutum " or hard plate on the abdomen. This is the case 

 with Dysderina, which has a wide distribution, as have also 

 Isclmyothyreus and Opopaea, and the non-scutate genus Orchestina. 



Fam. 10. Hadrotarsidae. This family contains only two 

 species, Hadrotarsus babirusa from New Guinea, and Gmogala 

 scarabeus from Sydney. In general appearance they resemble the 

 scutate Oonopidae, but they have eight eyes, curiously arranged, 

 two large, somewhat triangular eyes being situated near the 

 middle of the cephalothorax, and two groups of three small eyes 

 on either side of the front part of the caput. These spiders are 

 very minute. 



Fam. 11. Dysderidae. Six-eyed spiders, with long free 

 labium, and long maxillae provided with a well-developed scopula. 

 The cephalothorax is rather Jlat, and the abdomen is oval or 

 cylindrical, the integument being smooth and usually rather soft. 

 The palpal organ of the male is of simple structure. 



The Dysderidae are divided into two sub-families, DYSDERINAE 

 and SEGESTRIINAE, for the most part confined to temperate 

 regions. 



(i.) The DYSDERINAE are easily recognised by a peculiarity of 

 the sternum. Instead of being merely excavated along its border 

 for the reception of the legs, its edge is folded round the coxae 

 to meet the carapace, and thus forms a series of collars or sockets 

 in which the limbs are articulated in perfect isolation from each 

 other. These spiders vary considerably in size, and are gener- 

 ally of a somewhat uniform coloration, never marked with vivid 

 patterns. There are eight genera of this sub-family, two of 

 which are represented in England. 



Dysdera cambridgii is not a rare spider under stones in rocky 



