212 



28 (25) Sternum generally large. Intermediate plates of the combs 

 rather few in number, angular, and (at least most of them) larger 

 than the fulcra, and arranged in a single row. Hands broader than 

 high, in general large and depressed. [Principal lateral eyes three or 

 two; accessory eyes in general wanting, rarely one on each side. Sixth 

 joint of the tail nearly always destitute of a tooth or spine under the 

 sting.] Fam. IV. Pandinoidae. 



29 (32) The movable mandibular finger not only provided with a row of 

 teeth in the upper, but also with one or more teeth in the under mar- 

 gin. [Cephalothorax emarginate in front; dorsal eyes situated far in 

 front of the centre of cephalothorax; lateral eyes three, removed from 

 the lateral margin of cephalothorax. Sternum as broad as the labial 

 lobes of the second pair of legs together. Hands rather large, thick; 

 the hand-back x forming an obtuse angle with the upper surface of the 

 hand. Tail evidently keeled, its sixth joint long, not grooved on the 

 under side.] . Subfam. 1. Iurini. 



30 (31) The under margin of the movable mandibular finger armed with 



one strong tooth. The fine teeth along the middle of the edge of the 

 palp-fingers forming many short oblique rows Iurus. 



31 (30) The under margin of the movable mandibular finger provided 



with a row of (5) teeth. The teeth along the middle of the edge of 

 the palp-fingers forming a single continuous row . . . Uroctonus. 



32 (29) The movable mandibular finger provided with a single row of 



teeth, situated in its upper margin .... Subfam. 2. Pandinini. 



33 (52) Three principal lateral eyes on each side. 



34 (35) "Joints of the tail rounded, without keels." 2 . . . Dacurus. 



35 (34) Tail evidently keeled. 



36 (37) "A spine under the base of the sting." ..... Diplocenlrus. 



37 (36) No tooth or spine under the sting. 



38 (47) Lateral eyes removed from the lateral margin of cephalothorax. 



Hand-back forming an acute angle with the upper side of the hand. 



39 (46) Dorsal eyes not very far removed from the centre of cephalotho- 



rax. Under side of tail provided with three longitudinal grooves, and 

 with granules arranged in at least four longitudinal rows. Labial 

 lobes of second pair of legs together from half as broad again to 

 double as broad as sternum. 



40 (41) Cubitus rounded off anteriorly; its anterior side not separated by 



a strong margin or ridge from the upper and under surfaces. 



Heterometrus . 



i The hand-back is that surface of the hand which (in the family Pandinoidae) is 

 turned outwards, and which is bounded by the two strongest costte of the hand. 



2 According to Peters; C. L. Koch, however, says of his "Centrums''' [Dacurus] <jal- 

 binens: " The lateral keels and the inferior keels indeed present, but not very strongly 

 developed." The hands are said to be "narrow, uneven on the outside, without distinct 

 keels." Koch gives this species ten eyes ( ?) 



