//. ACER ATA: ARANEINA. 



451 



in long horny processes; the pedipalpi are tactile organs as in the 

 true spiders. The males possess a long penis, and the females a 



Fio. 466. — A phalangid laying eggs. (After Henking.) 



long ovipositor (fig. 4G6). They have two or four ocelli and 

 breathe by tracheae. 



These largely nocturnal animals are predaoeous, feeding upon small 

 mites. In structure tliey form in some ways an approach to the 

 Acarina. Phalangium* Liobunum* 



Legion II. 8j)hmro(jastrida. 



Arachnida with the abdominal somites fused so that no traces 

 of segmentation remain. 



Order I. Araneina. 



In the spiders the soft-skinned 

 body is divided by a deep con- 

 striction into cephalothorax and 

 abdomen (fig. 467). The four pairs 

 of legs are adapted for springing 

 or for walking, the hinder pair 

 being also accessory to the spin- 

 ning. It bears a comb-like claw 

 with which several threads are 

 combined into a stronger cable. 

 The chelicera bears a sharj) claw 

 (fig. 459), traversed by the duct 

 of the poison gland with which the 

 prey is killed, although but few 

 (species of Latrodectes, fig. 4GS, fig. 46: 

 the tarantula, and the bird spiders, 

 Mygalida;) can injure man. The pedipalpi are used as feeling 



Epeira rn.ndaris* round-web 

 fspider. (After Emerton.) 



