A Survey of the Scorpion Fauna of South Africa. 
Ill 
of carapace 12 mm., width of hand 3'5 mm., length of hand 14'25 mm., width 
of first caudal segment 7*20 mm., width of fourth caudal segment 7*6 mm. 
This species is a connecting link between P. plo,nicauda Poc. and 
P. flavidus Poc. The granulation on the upper surface of the first two 
caudal segments of planicauda is much finer than in kraepelini, but even in 
the former species, especially towards the posterior ends of those segments, 
the granules are often enlarged into short transverse ridges. In the first 
caudal segment of jplanicaiida the separation of the horizontal and descending 
portions of the upper surface is much more abrupt than in kraepelini : in 
the former case there is practically no excavation of that horizontal surface. 
13. P. STRIDULUS, Hewitt, Annals Trans. Mus. iv, p. 146, pi. xv, 1914. 
The type and only known specimen, a male, is from Luderitzbucht. The 
female is unknown, but I suspect that it agrees very closely with that of 
laevifrons Sim., to which the species is undoubtedly closely allied. 
14. P. TRiRADULATus, Hewitt (PI. XXI, fig. 33), Eecords Albany 
Museum, iii, p. 1, fig. 1, 1914. 
The types are from the Transvaal, north of the Zoutpansbergen. This 
species is closely related to, and possibly even identical with, P. truculentus, 
Hirst (24), based on an adult female from Loangwa, in Portuguese East 
Africa, and I think it is not unlikely that both may have to be included in 
the synonymy of mosamhicensis Ptrs. In trucidentus, the type of which I 
have examined, the median portion of the last tergite is rather coarsely 
granular, and in the posterior third mesially the granules are all transversely 
elongated into short stout ridges, yet none of these stretch across even half 
the breadth of the area : the four keels of the last sternite are more strongly 
developed than in triradulatus. It is prol^able, however, that the type of 
triradulatus is not fully grown. 
Key to the South African Species of the Genus Parahuthus. 
A. Sides and U7ider surface of the fourth caudal segment smooth or 
granular, but without distinct granular crests, (a and b.) 
(a) Sides and under surface of fourth caudal segment rather 
densely and finely granular ; inferior and inferolateral 
keels of second and third caudal segments composed of 
coarse granules which increase in size posteriorly as the 
keels themselves converge, whilst in the third segment, and 
to a less extent in the second, the inferior lateral keels are 
connected along the posterior margin of the segment by a 
pair of large ridge-like granules, thus forming a y -shaped 
crest ; movable finger only a little longer than the hand- 
back. A small species, the type female reaching a total 
length of 50 mm. . P. brevimanus Thov. 
(b) Lateral and inferior surfaces of the tail smooth between the 
keels, but on the fourth and fiftli segments with a few 
