SCORPIONS OF THE aENITS ISOMETRTIS. 447 



keels on the fifth caudal segment less developed, and iutlie slight 

 basal separation of the dactyli. 



~ Measurements in millimetres. — $ . Total length 30 ; cephalo- 

 thorax, length 3'5, width 3"8 ; length of tail 17"3, of first two seg- 

 ments 4'3, of fifth 4'5, of vesicle and aculeus 4*2 ; width of first 

 segment 2-2, of fifth 2 ; length of humerus 3, of brachium 3"7 ; 

 width of brachium 1"4, of manus 1'2 ; length of " hand-back " 

 2, of movable dactylus 3*5. 



S . Total length 36"5 ; cephalothorax, length 3'8 ; length of 

 tail 23, of first two segments 6, of fifth 6, of vesicle and aculeus 

 4-2 ; width of first segment 2-2, of fifth 1-7 ; humerus, length 3*7 ; 

 brachium, length 4'5, width 1-5, of manus 1"5 ; length of " hand- 

 back " 2*3, of movable dactylus 4. 



The Museum has two specimens, a female from Angola {Dr. 

 Welwitsch), and a male from the Congo, collected by Andrew 

 Curror, Esq., Surgeon E,.N. 



This species appears to be allied to Tityus clathratus, C. Kocb, 

 a species from the Cape of Grood Hope, which is very likely refer- 

 able to the genus Isometrus. But in T. clathratus the superior 

 caudal keels are much elevated and strongly toothed. 



I can make nothing of the description of LycTias onabillanus, 

 Eochebrune *. This species is recorded from Gambia and declared 

 to be different from Lyelias yabonensis( = I. maculatus, De Greer). 

 At all events it at least differs from I. asper in having twenty 

 pectinal teeth. 



EXPLANATION OF PLATE XI 



Fig. 1. Isomctnts tricarinatus, Simon, (J, nat. size. 



1 a. „ „ tail of c? . 



1 b. „ „ tail of $ . 



1 c. ,, ,, hand of (j*. 



Id. „ „ hand of §. 



2. „ Hosei, sp. n., § , nat. size. 



3. ,, ai'inatus, sp. n., §, nat. size. 

 3 a. „ „ hand of § . 

 3 b. „ „ hand of cJ • 



3 c. „ „ tail of 5 . 

 3d. „ „ tail of c?. 



4. ,, serratus, sp. n., (^, nat. size. 



4 a. „ ,, hand of (^ . 

 4 6. „ „ tail of c?. 



5. „ Burdoi, Simon, § , nat. size. 



Bull. Soc. Philom. (7) viii. p. 28 (1884). 



