ABTHEOPOD FAUNA OF THE WEST INDIES. 399 



Greniis Beoteochactas, PococJc, 



Ann. 3Iag. Nat. Hist. (6) xii. pi. v, figs. 2, 3. 



Anterior border of carapace very lightly depressed in the 

 middle, but not excised. The lateral eyes two in number ; the 

 anterior close to the margin of the carapace, the posterior a little 

 above it, not or but little prominent. The tubercle of the 

 median eyes far in front of the middle of the carapace. 



Sternum wider than long, of the pentagonal type ; its posterior 

 border widely emarginate, equalling in width the maxillary lobes 

 of the second coxse. 



JPectlnes short. 



Stigmata oval. 



The movable digit of the cJielicercB not terminating in two 

 subequal fangs, the upper one being short. 



Palpi short, robust. 



Tail robust, anteriorly smooth beneath. 



Loiver surface of the terminal tarsal segment of the legs orna- 

 mented with spiuiform hairs, which are arranged more or less 

 distinctly in two series. 



Differs from Chactas in that the front of the carapace is not 

 emarginate, the lateral eyes not prominent, the lower surface of 

 the feet not compressed and uot armed with a single series of 

 spines, &c. 



22. Beoteochactas nitidtjs, PococJc. (PL XXIX. figs. 7-7 a.) 



2 • Colour castaneous ; legs, vesicle, and lower surface a little 

 paler. 



Carapace perfectly smooth and polished, marked with a Y- 

 shaped groove, the two upper arms of which embrace the ocular 

 tubercle ; the anteocular portion not mesially depressed, the 

 lateral portion sloped away. 



Tergites perfectly smooth and polished, marked in front on 

 each side of the middle with a shallow depression ; the last 

 tergite with four tubercles (sometimes six) correspondiDg to the 

 four superior keels of the tail-segments. 



Sterna smooth and polished. 



Tail robust, uarrowed towards its distal end, the upper surface 

 smooth and polished, the first segment scarcely excavated longi- 

 tudinally, the excavation increasing in depth to the fourth, the ' 

 fifth flat posteriorly, excavated in front, the supero-lateral keels 



