1899.] AND SPIDERS FROM TROPICAL WEST AFRICA. 859 



Legs short ; patella and tibia of 1st less than width of head. 



Abdomen without inferior tubercle; the anterior lateral spines 

 minute and lying far back behind the middle of the scutum 

 and justiu front of the posterior laterals, from the supporting pro- 

 minence of which, however, they are separated by a rounded notch ; 

 the anterior border lying between these anterior spinules widely 

 and nearly evenly convex, forming an almost completely semicircular 

 arch defined by the normal 10 sigilla, of which the 4 medians form 

 a straight transverse line ; posterior lateral spines erect, very short, 

 but borne upon the summit of a thick cylindrical prominence, the 

 axis of which cuts that of the spines at an obtuse angle; posterior 

 spines resembling the posterior laterals, but their axis in a line 

 with that of the prominence and directed straight backward. 



Measurements in millimetres. — Total length of abdomen along 

 middle line 6 ; width just in front of anterior spinule 9*5 ; width 

 from tip to tip of postero-lateral spine 8. 



Loc. Benito Eiver {Q. L. Bates). 



This species seems to form a new section of the genus Gastera- 

 cantha. 



GrASTEEACANTHA (^trocantha) eogeesi O. P. Cambr. 



Gasteracantha rogersi, O. P. Cambr. P. Z. S. 1879, p. 292, fig. 23 

 (c?). 



Gasteracantha (^trocantha) semijlava, Simon, Ann. Soc. Ent. 

 Fr. 1887, p. 268, pi. vi. fig. 2 ( ? \ 



Loc. Sierra Leone. 



Described from Assinie by M. E. Simon, and from Coanza by 

 O. P. Cambridge. 



■'o^ 



Gasteracantha (Isoxia) penizoidbs Simon. 

 Isoxia penizoides, Simon, Ann. Soc. Ent. Pr. 1887, p. 269, pi. vi. 

 fig. 4. 



Loc. Benito Eiver (G. L. Bates). 

 Eecorded by Simon from Assinie. 



The foregoing species of Gasteracantha may be tabulated as 

 follows : — 



a. Lower side of abdomen with large conical tubercle ; spines 



large. 



«.i. Anterior and median spines subequal and in contact connata. 



h^. Anterior and median spines unequal and widely separated. 



a^. Spines with strong recurvature curvispina. 



b^. Spines not or scarcely recurved formosa. 



b. Lower side of abdomen without tubercle; spines absent or 



short. 

 0.'. Spines present. 



a*. Anterior border of abdomen widely convex ; anterior 

 spines lying far back close to and much smaller than 



the median spines ; head tuberculate above bat est. 



6*. Anterior and lateral borders of abdomen cutting at right 

 angles the anterior spines, as large as the medians and 



widely separated from them ; head not tuberculate rogersi. 



b". Spines absent ; abdomen widely rounded behind penizoides. 



