Classification of Scorpions. 311 



Sternum reduced to a transverse anteriorly angularly con- 

 vex and posteriorly concave sclerite, transversely but scarcely 

 longitudinally impressed, wedged in between the genital oper- 

 culum and the ingrown coxse of the appendages of the fourth 

 pair. 



Genital operculum large. 



Pectines moderately or very long, with clearly defined 

 fulcra and intermediate lamella. 



Appendages. — The penultimate tooth on the movable digit 

 of the chelicerge very short ; the digits of the chelge not angu- 

 larly notched ; the denticles arranged in three series — an 

 external and internal, consisting of larger separated teeth, and 

 a median, consisting of a single or double, rarely [Cerco- 

 phonius) a multiple series of smaller teeth. 



Feet with two pedal spurs (rarely the posterior obsolete, 

 Phoniocercus) ; the lower surface furnished with more or 

 fewer lateral spines and a median series of hairs or spicules. 



Tail mostly powerful, its keels largely obsolete, with no 

 spine beneath the aculeus. 



^ (? in all genera) with a tooth on the inner surface of the 

 hand ; digits not lobate. 



$ with cleft genital operculum. 



Genera : Bothriurus^ Peters ; Brachistosternus, Pocock ; 

 CercophoniuSy Peters ; Mecocentrus, Karsch j P/ionio- 

 cercusj Pocock ; Thestj/lus, Simon j Timogenes^ Simon ; 

 Urop)honiuSj Pocock. 



Distribution. S. Neotropical, Australia, Sumatra. 



The scorpions of this group seem to be little more than an 

 exaggeration of some of the American members of the lurini, 

 for some of them show many points of resemblance to Cara- 

 boctonus and Uadrurus. 



Family ButhidaB, Simon. 



Feet furnished with two pedal spurs, the anterior of which 

 is often double. 



Sternuvi small, triangular or pentagonal. 



Ocular tubercle in front of the middle of the carapace ; 3 to 

 5 lateral eyes on each side. 



The movable digit of the cheliceraj with the penultimate 

 fang subequal to the terminal ; its inferior edge armed with 

 teeth ; the lower edge of the immovable also generally armed. 



Tlic hands of the ])alpi arc rounded and the digits long. 



S . With the tail and palpi usually longer and thinner or 



