Superfamily Avicularioides. 



these spiders live in regions that have been explored compara- 

 tively little, and as many of them are perfectly concealed in their 

 nests during the day time, doubtless many other species remain 

 to be discovered. 



Our known species represent five subfamilies; these can be 

 separated by the following table. 



TABLE OF SUBFAMILIES OF THE AVICULARIID/E 



A. Postabdomen situated immediately above the spinnerets; 

 furrow of the chelicerae well-marked; median furrow of 

 the thorax transverse or elliptic. 

 B. Tarsi of legs not furnished with a bundle of terminal 

 tenent hairs; scopulae often wanting; third claw almost 

 always well-developed. 

 C. Chelicerae furnished with a rake; hind spinnerets 

 rather short and with the last segment short and 

 obtuse. P. 231. Ctenizin^ 



CC. Rake of the chelicerae wanting; hind spinnerets long 

 and with the last segment slender. P. 247. 



Diplurin^e 



BB. Tarsi of legs furnished with scopulae and with a bundle 



of terminal tenent hairs - third claw wanting or obsolete. 



P. 241. Aviculariin^e 



AA. Postabdomen situated a considerable distance above the 



spinnerets; furrow of the chelicerae indistinct; median 



furrow of the thorax longitudinal. 



B. Chelicerae furnished with a rake. P. 248. 



BRACHYBOTHRIINy'E 



BB. Rake of the chelicerae wanting. P. 251. Hexurin/E 

 Subfamily CTENIZINiE (Cten-i-zi'nae) 



The Trap-door Spiders 



The trap-door spiders resemble the tarantulas of the two 

 following subfamilies in having the postabdomen situated imme- 

 diately above the spinnerets, in that the furrow of the chelicerae 

 is well-marked, and in that the median furrow of the thorax is 

 transverse or elliptic. They are distinguished from the bird- 

 spiders in lacking a bundle of terminal tenent hairs on the tarsi 



231 



