AVICULARIIDAE 389 



Their burrows are often surmounted by a sort of turret raised 

 above the level of the ground. 



(v.) Tlie Barychelinae are burrowing forms whicli resemble 

 Kemesia, but have only two tarsal claws. Lcptoi^ehna is the 

 only European genus, and has close affinities with certain South 

 American genera {Psalistops, Euthycoelus, etc.). Fisenor inhabits 

 tropical Africa, and Diplothele, unique in possessing only two 

 spinning mammillae, is an inhabitant of India. 



(vi.) The AvicULAPJiNAE include all the large hairy spiders 

 wiiich are commonly called. Mygalc. The genus Plilogius, which 

 inhabits Southern Asia, forms a lidless burrow, thoug-h it has no 

 rastellus, but practicall}' all the other members of the group are 

 uon-terricolous, living under stones or in holes in trees, where 

 they weave a slight web. They are nocturnal in their habits. 

 They all possess two tarsal claws, and the lal)ium is free and 

 spined at the tip. Of the four spinnerets the posterior pair are 

 long and three-jointed, while the anterior are short and not very 

 close together. 



The particular form of the tarsi and the nature of the 

 scopulae,^ " claw-tufts," and spines upon them are of great import- 

 ance in distinguishing the members of this group. 



The Aviculariinae comprise about sixty genera from all the 

 tropical and sub-tropical regions of the world. 



The genus Ischnocolvs extends into the Mediterranean region, 

 having representatives besides in Southern Asia and in Central and 

 South America. All the tarsi have their scopulae divided longitudin- 

 ally l:)y a band of hairs. Chaetojjelma inhabits Egypt, Syria, and 

 Araljia, and Cydosternum is found in West Africa as well as in 

 Central and South America. In these genera the scopulae of the 

 last two pairs of legs are alone divided. The largest known 

 spider is Theraphosa leUondi, which is a native of Guiana. It 

 measures 9 cm. (about three and a half inches) in length. 



Unrypehna is a genus of large spiders entirely confined to 

 the Xew World, where it possesses many species. The genus 

 Avicularia is also American, and includes a number of large 

 long-haired spiders with short and very strong legs, on which 



^ The " scopula " is the pad of close-set thick hairs which covers the under 

 surface of the tarsus and often of the metatarsus. The " claw-tufts " are groups of 

 longer hairs, often extending beyond the claws, and giving the foot a bifid appear- 

 ance. 



