120 



NATURAL HISTORY OF ARTHROPODS. 



The DBASSID^E is a large family, which has the eight eyes arranged in two rows. 

 There is considerable variation in the relative length of the limbs, but the two middle 

 pairs are shorter than the first and last. The species are mostly dull-colored, and live 

 under stones, or in silk tubes on plants, but all do not spin a web for the capture of 

 their prey. We have already referred to the habits of the water spider of Europe, 

 Argyroneta aquatica. 



In the species of Drassus the feet terminate with two claws and a bundle of flat- 

 tened hairs. Tegenaria domestica is the common house-spider, which has followed 

 man from the old to the new world. The species of Clubione are nocturnal in their 

 habits. A favorite place for their silken tubes is under the loose bark of trees or 

 between the boulders of a stone wall. Many species are known. The family CINI- 

 FLONID^E has been separated from the last on account of its peculiar spinnerets. 



The family DYSDERTDJS is an exception to the rule, as its members have but six eyes, 

 and a closely allied Cuban form (Nops guancibacoce) has but two. The first pair of legs 

 are the longest. The species are few in number, and the American forms are far from 

 common. They are usually found under stones, but can move very quickly when so in- 

 clined. 



SUB-ORDER II. - - TETRAPN.EUMONIA. 



This group, which, as its name indicates, possesses four pulmonary sacs, embraces 

 the largest spiders known. It is composed of a single family, MYGALID^S. The man- 

 dibles are very large, and work up 

 and down instead of laterally. 

 The eyes are always eight in 

 number, and are placed close 

 together. Mygale is the best 

 known genus. It is a native of 

 tropical and semi-tropical Amer- 

 ica. The large Bird spider of 

 Surinam reaches a length of two 

 inches. The body is a pitchy 

 black, and is covered with long 

 reddish-brown hairs. It is said 

 that it catches small birds, kills 

 them with its poisonous bite, and 

 then sucks their blood. Mygale 

 hentzii is a not uncommon species 

 in the Southwestern States. The 

 genus Cteniza contains the Trap- 

 door spiders, of whose wonderful 

 architecture an account has been 

 given in the preceding pages. 

 The two best known species are 

 Cteniza ccementaria, of Southern 

 Europe, and C. californica, of 

 California. Atypus is another 

 genus of the family which lives further north. According to Mr. J. Wood-Mason 

 some of the large Indian Mygalidse are possessed of organs for producing a noise. 



FIG. 173. Mygale hentzii. 



