TULLGREN, ARANEiE FR. THE GRAN CHACO. 45 



Oxysoma Nic. 



Simon, Hist. nat. d. Araignées T. II, fasc. 1, 1897, pag. 100. 



O. liiieatiim n. sp. (Pl. 6, fig. 20). 



Female. — Cephalothorax elongate-oval, with a very in- 

 distinct central-furrow and nearly effaced cephalic and tho- 

 racic strise. In the middle line on the yellowish ground- 

 colour a broad in front effaced brownish red band and on 

 each side of that four punctiform short blackish stripes, 

 Clypeus with two small transverse spöts of brownish coloiir. 



Eyes. — Anterior row straight with lateral eyes twice 

 as large as central ones. Central eyes about their radius 

 apart and the distance from anterior laterals shorter. Area 

 of central eyes much longer than broad and much narrower 

 in front than behind; posteriors much larger. Posterior row 

 much broader than anterior one with the eyes about equal 

 in size. Posterior centrals nearly 1^/2 their diameter apart 

 and the distance from laterals a little shorter. All eyes 

 surrounded by black rings. Clypeus about as high as the 

 diameter of anterior lateial eyes. 



Cheliceres long cylindrical, testaceous yellow with a nar- 

 row reddish brown stripe along the front-side. Inner margin 

 of the fang-groove with two equal, stout teeth. 



Coxce of pedipalp and labium testaceous. 



Sternum elongate-oval, tapering behind, testaceous. 



Legs 1. 4. 2. 3. testateous yellow witli very small strewed 

 redbrown spöts especially on femur, patella and tibia. Tar- 

 sus and metatarsus with a short but thick scopula. Nume- 

 rous long blackish spines. Claws 2 with 6 long denticles on 

 the first pair of tarsi. 



Ahdomen very elongate, a little truncated in front and 

 longly tapering behind. Colour testaceous gray in the middle 

 line of the back a narrow indistinct band of reddish-brown 

 colour, that behind consist of more or less /\-shaped mar- 

 kings. Venter without spöts. The rima ventralis situated a 

 little behind the middle of the venter. Abdomen as well as 

 all other parts of the body with a short grayish pubescence. 



Vulva comparatively small, broader than long. In the 

 middle of front a short oval depression, backwards limited 



