Classification of Scorpions. 307 



Sternum longer than wide, its sides parallel or slightly 

 converging anteriorly. 



The penultimate tooth on the movable digit of the cheli- 

 cerse small, very rarely approaching tlie size of the terminal. 



Digits of the chelae with their opposable edges angularly 

 notched. 



Bases of the claws of the legs concealed laterally by lobate 

 expansions of the extremity of the feet ; feet furnished 

 beneath with two subparallel series of strong spines (the 

 anterior series sometimes obsolete, e. g. Mkephonus). 



Pectines of medium length. 



Tail powerful or moderately so, without a spine beneath 

 the aculeus. 



In the male the tail and chel^ are often elongate, the 

 hands being thinner than in the female ; the digits, however, 

 do not appear to be lobate and sinuate basfUy as in many 

 other scorpions. 



Genera: Scorpio^ Linn. ; Reterometrus, Hempr. & Ehrenb. ; 

 Micephonusj Thor. (syn. Mossamedes, Sim.) ; Q^co- 

 petrus, nom. nov.*, OpisthopJitlialmuSy C. Koch j 

 PalamnceuSj Thor. 



Distribution. Ethiopian and Oriental Regions. 



Subfamily Iscrnurini. 



Eesembling the Scorpion ini, but differing in having : — 



The_yee^ not distally lobate and not armed beneath in the 

 same way. 



The penultimate fang of the chelicercB subequal to the 

 terminal. 



The sternum very wide, with parallel or diverging sides. 



The pectines usually shorter. 



The tail weaker and distinctly compressed. 



Characters of male as in the Scorpionini, except that the 

 digits are generally lobate and sinuate at the base. 



Genera : Ischnurus^ Gervais ; Opisthacanthus, Peters ; 

 OpjisthocentruSy nov. ; Cheloctonus, Pocock ; Ghiro- 

 maclius^ nov. ; Hormurus, Thorell ; lomachus^ nov. 



Distribution. Ethiopian, Oriental, Australian, and North 

 Neotropical Regions. 



Subfamily Diplocentbini. 

 Differs from the Scorpionini in having : — 

 A distinct tubercle beneath the aculeus of the tail. 



* For Pdrooicus, Karscli, preoccupied as Pelroica {Petncca) in Aves. 



