72 
Annals of the Transvaal Museum 
the male of Hexisopus lanatus but only indistinctly in the female: thoracic 
spiracles very large. There is a general absence of bristles or stiff hairs on the 
surfaces of body and appendages, but numerous long soft and low-lying hairs 
occur. 
Key to the S. African species of Genus Chelypus . 
1. Shaft of flagellum directed forwards, upwards, backwards, and 
downwards in a bold curve, the apex bifid, with a short tooth-like medial 
branch and a longer lateral branch. Dorsal surface of upper jaw with 
two very large black tubercles distally. Tibia of fourth leg longer than 
the tarsus, and broader than the patella, but not lobed : tarsus of fourth 
leg broader than long. Claws of second and third leg composed almost 
entirely of the distal segment, the proximal segment (claw peduncle) 
being extremely short and indistinctly marked off. C. barberi Purcell. 
2. Similar to barberi but flagellum not bifid at the apex but tapering 
to a point. C. hirsti Hewitt. 
3. Dorsal surface of upper jaw with only one large tubercle. Tibia 
of fourth leg with a large rounded lobe projecting externally and densely 
covered with short spinules. Tarsus of fourth leg longer than broad. 
Distal segment (claw proper) of tarsal claw of third leg less than half the 
total length of the claw and distinct^ marked off from the proximal 
segment (claw peduncle). C. lennoxae Hewitt. 
