TULLGEEN, ARANEJE FR. THE GRAN CHACO. 



Chaco n. g. 



Tliis genus belongs to the subfamily Brachychelinge and 

 the group Lept opelnia t ae and seems to me to be most related 

 to the genus Euthycaelus Sim. From that it differs in some 

 important characters especially by having the two apical 

 joints of the superior mamillse equal in length and by the 

 labium, that is perfectly without spines. Through this latter 

 character it agrees with the genus Trichopelma and Cosmo- 

 pelma but the superior tarsal claws are furnished with two 

 rows of small denticles. 



Cephalo thorax clothed with short adpressed hairs and 

 with a deep and nearly straight central fovea. Cephalic area 

 comparatively low. The ocular tumulus low and broader 

 t han long. The diagram of eyes as by Euthycaelus. The 

 rastellum composed of numerous short irregularly arranged 

 spines. Coxa of pedipalp a t the base with numerous short 

 cusps. The two first pairs of tarsi and metatarsi densely 

 scopulate; the posterior ones slightly clothed beneath with 

 scopuliform hairs and in the middle-line with a row of spini- 

 form hairs. 



C. obsciira n. sp. 



Female. — Cephuloihorax longer t han broad. Cephalic 

 area comparatively low, occupying nearly two-thirds the 

 length of cephalothorax. Cephalic strise distinct, thoracic 

 ones nearly effaced. Colour dark reddish brown, with short 

 grayish yellow pubescence. Central fovea deep and very 

 slightly recurved, nearly 2 mm. in length. 



Eyes situated on a high ocular tumulus in front furni- 

 shed with long curved spiniform hairs. Median and highest 

 part of tumulus. projected forwards. First row of eyes slightly 

 procurved. Anterior central eyes circular, about a diameter 

 apart, less than half a diameter from anterior laterals. An- 

 terior laterals ellipsoidal, their axes a third longer than dia- 

 meter of anterior centrals. Posterior central eyes ellipsoidal, 

 smallest, about their axes from anterior centrals, not one- 

 half the träns verse diameter from posterior lateral eyes. 

 These latter ones ellipsoidal, their axes almost equal to those 



