ANNULOSA. 557 



ploy them as a rope, on which to convey themselves •. The 

 species feed on flies, and, in some instances, on mineral sub- 

 stances. Mr Holt found, that the Aranca (Salticus) 

 scenica devoured the sulphat of zinc, and by the process of 

 digestion deprived it in part of its acid -f-. The sexual or- 

 gans of the male are double, complicated externally, and 

 lodged in a cavity of each palpus. Those of the female are 

 placed on the belly between the stigmata. 



1. Mandibles with their liooks Jblded transversely. 



This includes the genus Aranea of Linn.eus, now form- 

 ed by Walkenaee, Latjieille, and others, into the fol- 

 lowing genera : 



(1.) Segestria, Dysdera, Clotho, Aranea, Filistafa, 

 Drassus, Clubiona, Argyroneta. (2.) Scytodes, Theri- 

 dium, Episinus, Pholcus. (3.) Linyphia, Uloborus, Te- 

 tragnatha, Epeira. (4.) Sparassus, Selenops, Thomisus. 

 (5.) Ctenus, Sphasus, Dolomedis, Lycosa. (6.) Eresus, 

 Salticus. 



% Mandibles with their hooks folded ventrally. This 

 includes the following genera : Mygale, Avicularia, Aty- 

 pus, Eriodon. 



B. Palpi large, unconnected with the sexual organs, 

 which are seated at the base of the abdomen. Anus desti- 

 tute of spinners. 



1. Abdomen pedunculated. Stigmata two. This in- 

 cludes the genera Thelyphonus and Phrynus. 



2. Abdomen sessile. At the base, behind the legs where 

 it joins the thorax, are two diverging pectinated scales, and 

 it terminates in a jointed tail, with a poison sting. The 

 stigmata are eight in number. This includes the genera 

 Scorpio and Buthus. 



■ Annals of Phil. vol. ix. p. 306. f lb. vol. xii. 454. 



