Annals op the Transvaal Museum. 
189 
[A. hamiltoni Pocock, from Vredefort Road is based on a very young 
example : it belongs to my section A.] 
Galeosoma robertsi , sp. nov. (Plate XXVI, figs. 3 and 4.) 
Types. — This description is based on a large series of adult female 
examples collected during March and April, 1915, by Messrs. A. Roberts 
and G. van Dam from the following localities, all in the Pretoria District : 
Mayville, Wonderboom Poort, New Muckleneuk, Hatfield, Pretoria College, 
Brooklyn, Bon Accord Station, Garstfontein, Rietfontein (near Crocodile 
River Bridge), Elandsfontein No. 35, and Skinner’s Court. It is note- 
worthy that another species, pilosum, is commonly found in the immediate 
neighbourhood of Pretoria, apparently occurring side by side with robertsi . 
Abdominal shield. — The upper surface of the shield is very strongly 
curved from side to side, but less curved in a longitudinal line : on a 
transverse vertical section across the middle of the shield, the cut edge 
of the upper surface would show an almost semicircular outline. Viewed 
from above, the upper surface is broadly oval. Viewed from the side, 
the line of junction between the upper and marginal surfaces is not straight, 
but curved forwards considerably in the middle. The marginal surface 
is nowhere deep : it is deeper anteriorly than elsewhere and is usually 
most reduced laterally : throughout it is definitely marked off from the 
upper surface and, except immediately at the posterior end, its surface 
is free from the coarse punctuations which cover the whole of the upper 
surface. However, the line of junction between the two surfaces does, 
not usually form a very strongly-defined continuous ridge. A definite 
ridge occurs posteriorly, yet its continuation forwards is not along the line 
of junction between the two surfaces, but for a short distance along the 
lateral portion of the dorsal surface on each' side : this ridge is feebly 
developed and usually occurs only in the posterior half of the shield, but 
in one of the Rietfontein specimens extends well into the anterior half 
of the shield. In a small specimen from Elandsfontein, and in two immature 
examples from Skinner’s Court, the line of junction between the two 
surfaces forms a sharp, slightly-upturned, continuous ridge all round. 
In two examples from Garstfontein the ridge, which in specimens from 
other localities occurs in the posterior half of the shield, is quite absent 
and the marginal surface posteriorly becomes almost completely reduced. 
The upper surface is polished and has no long hairs nor setae. 
Immediately in front of the shield, on the dorsal surface of the abdomen, 
the soft skin presents several well-defined transverse rows of short setae, 
whilst ventrolaterally the oblique lines of setae are strongly developed. 
Carapace without long bristly hairs on any part of its surface or with 
only one or two on the head region dorsolaterally or between the eyes. 
Measurements. — Total length 18 mm., length of carapace 7, breadth 
of carapace 5 *25, length of upper surface of shield 9 -5, breadth of upper 
surface of shield 7-75. 
This species is probably closely related to G. scutatum , Pure., from 
Krugersdorp. As already indicated in the description, a considerable 
variation exists in the development of the demarcation line between the 
upper and lateral surfaces, but in scutatum no such line occurs.. 
