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Transactions of the Royal Society of South Africa. 
granules below ; upper surface of first caudal segment 
flattened, projecting step-like, and then suddenly descending 
perpendicularly at the anterior margin of the very broad 
shagreened area ; brachium slender, 2|-3 times as long as 
wide ; movable finger about 2-^ times as long as the hand- 
back ; carapace much wider than long ; tail of male unusually 
thick ........... P. calvus Pure. 
B. Fourth caudal segment with 8 or 10 granular crests, (c — p.) 
(1) The granular area on the dorsal surface of the second caudal 
segment not reaching to the hind edge of the segment, (c — g.) 
* The middle lateral crest on the fourth caudal segment weah 
or rudimentary, except towards the posterior end of the 
segment, (c.) 
((') Upper surface of first caudal segment not flattened but 
holloAved out from side to side, the narrow shagreened area 
not projecting step-like anteriorly, but descending gradually 
in a median groove ; granular area on the dorsal surface of 
second caudal segment three or four times as long as wide ; 
fourth and fifth caudal segments densely granular below ; 
brachium slender, its length 2|-3 times its width ; carapace 
much wider than long ; vesicle comparatively small. Trunk 
and tail dark reddish brown ..... P.granulatus^.Sa'E. 
The middle lateral crest on the fourth caudal segment 
coarsely granidar, fairly strong and well developed, 
(d-g-) 
t Dorsolateral keel of fifth caudal segment practically con- 
tinuous throughout, although more or less irregular in 
the middle, the accessory dorsal crest composed of 2-4 
sharp pointed teeth, the posterior one of which is higher 
than broad, (d and e.) 
(d) Tail strongly pilose ; fourth caudal segment narrower than 
the first ; granular area on upper surface of second caudal 
segment occupying' a deep oval depression in the anterior 
two-thirds of that surface ; of first caudal segment very 
large, almost flat or only slightly concave, and at its pro- 
jecting anterior edge suddenly descending perpendicularly 
in the middle ......... P. villosus Ptrs. 
(e) Tail sparsely hairy ; fourth caudal segment wider than the 
first ; granular area on upper surface of second caudal 
segment occupying an oval excavation in the anterior half - 
of the surface ; of first caudal segment as in villosus, but at 
its anterior edge the surface descends less abruptly and the 
angle is slightly more obtuse than in that species . P. schlechteri Pure, 
ft Dorsal keel of fifth caudal segment brolcen and indistinct 
in the middle, the accessory dorsal crest composed of 
blunt tubercles or short teeth ivhich are not higher than 
broad, (f and g.) 
(/) Last sternite with a pair of median keels ; last tergite in 
its mesial area covered Avith a close shagreen composed 
of j^'ranulos which are smaller than those found on the 
