Annals of the Teansvaal Museum. 
187 
that of grandis, the posterolaterals being nearer to the medians than are 
the latter to each other. Band of spines on patella IV only reaching J-J 
of the distance along the segment ; band of spines on anterior surface of 
tibia II, including 10-13 spines. 
Acanthodon cp. oomi Hewitt (Records Albany Mus., II, p. 416). 
Mr. A. Roberts took female examples very closely related to oomi 
at Lake Chrissie and Tevreden and a small example also at Oshoek, Carolina 
District. They differ from the type of oomi in the ocular arrangement : 
in the type, the pair of long spines behind the ocular area is situated just 
midway between the fovea and the anterior margin of the anterior median 
eyes, but in the above specimens is nearer to the anterior medians than to 
the fovea. The ocular area is m fact a trifle shorter relatively in these 
specimens than in the type. There is also a strong resemblance to 
A. crudeni from Alicedale, but the intervening spaces between the eyes 
of the posterior row, compared with the size of the posteromedian eyes, 
are distinctly greater in these examples than in crudeni. 
Key to the South African Species of the genus Acanthodon , based on the 
characters of the Adult Females. 
A. — A strip of rather slender setae on the post-ventral border of coxa III. 
(a) Ocular area short, its length less than or not exceeding f of the 
distance from the anterior margin of the carapace to the centre 
of the fovea. 
(1) Frontal eyes about a diameter apart. Abdomen without seti- 
gerous tubercles superiorly. (Kentani.) A. spiricola Pure. 
(2) Frontal eyes about a diameter apart. Abdomen with seti- 
gerous tubercles superiorly. (Kentani.) A. Jcolbei Pure.* 
(3) Frontal eyes about \ of a diameter apart and projecting 
strongly forwards from the front margin of the carapace. 
Distance between posterior medians about equal to twice the 
diameter of an eye. (Grahamstown.) A. flaveolum Poc. 
(b) Ocular area a trifle longer, just exceeding in length f of the 
distance from the anterior margin of the carapace to the centre 
of the fovea. 
(4) Frontal eyes about of a diameter apart, the distance between 
the posteromedians equal to If times the diameter of an eye. 
Posterior medians decidedly nearer to the posterior laterals 
than to each other. (Alicedale.) A. crudeni Hewitt. 
(c) Ocular area still longer, almost equalling in length § of the distance 
from the anterior margin of the carapace to the fovea. 
(5) Frontal eves about f of a diameter apart : posterior row of 
eyes equally and rather widely spaced : patella IV strongly 
spined anteriorly to the apex : strip of setae on coxa III very 
weakly developed. (Liineburg.) A. oomi Hewitt. 
(6) Frontal eyes nearly | of a diameter apart : strip of setae on 
coxa III strongly developed : patella IV spined anteriorly 
* This species is not known to me. 
