Mr. R. I. Pocock on East-African Scorpions. 429 



deeply infuscate, especially towards its extremity, though the 

 upper surface and the vesicle is reddish. The sexes are 

 easily distiiii^aishable ; in the female the hand is barely as 

 wide as the brachium, its width being about one third the 

 length of the movable digit * ; the two digits are straight and 

 in contact ; the first segment of the tail is the widest, but 

 the second, tliird, fourth, and fifth are equal in width ; the 

 pectines are short and furnished with 18 or 10 teeth. The 

 largest female measures 66 millim., the carapace being almost 

 7 and the tail 37. In the male, on the contrary, the hand is 

 much wider than the brachium (3 : 2), its width being nearly 

 half the length of the movable digit, which is slightly lobate 

 at the base, while the immovable is somewhat strongly 

 sinuate ; the tail is wider than in the female, being almost 

 parallel-sided, the fourth and fifth segments equalling the 

 width of tlie first and slightly exceeding that of the second. 

 In both sexes the tails are perfectly smooth to the touch, 

 though in reality they are exceedingly finely granular, with 

 very weak keels. The pectines are longer, with 19 or 20 

 teeth. Length of largest male 54 millim., of which the cara- 

 pace is 5*8 and the tail 33. 



The examination of these forms has shown me that 

 B. Kirhiiy Poc, the type of which, though decolorized, shows 

 the dark-tinted brachium characteristic of the West-African 

 species, is closely allied to B. Biittneri, from which it appa- 

 rently differs merely in the greater exaggeration of its sexual 

 features, as evidenced by the greater width and smootimess 

 of the tail. If such characters increase with age I could well 

 believe the type of B. Kirkii to be nothing but an aged 

 individual of B. Biittneri. 



In the footnote to my description of B. Kirkii mention is 

 made of a couple of examples of a scorpion from Rio del Rey 

 near the Old Calabar River, which were referred to B. Biitt- 

 neri; but since seeing the examples mentioned above from 

 Cette Cama I am compelled to change my opinion about the 

 identity of the Rio del Rey examples ; and since they are 

 both readily distinguishable either as subspecies or species 

 from the Cette Cama form which apparently comes nearest 

 to the typical B. Biittneri^ I propose to describe the former as 

 a new species under the name Balycurus Johnstonii. As 

 stated in the synopsis below, this form is much darker coloured 

 than Biittneri, the legs, hand, humerus, and upper surface of 



* On this digit there are eight median rows of teeth, the basal one 

 being long and undivided ; the outer row consists also of eight, but the 

 inner of nine, owing to the presence of one near the middle of the basal 

 row of the median series. 



