Annals of the Transvaal Museum 
49 
keel. Flagellum strongly flattened from front to back at the anterior 
bend, being as wide as the fang itself at this point, or nearly so. 
Shaft of flagellum filiform throughout. 
26. Flagellum reaching back a little beyond the ocular tubercle and 
slightly blunted at the tip : the anterior bend situated far forwards, overlying 
the most distal tooth: basal enlargement very high, the whole upper margin 
elevated as a high laminar keel. On the inner side of the upper jaw, near to 
the anterior bend, is a distinct dorsal tooth pointing forwards. Two distal 
teeth of upper jaw moderately large, and in front of these is a more or less 
distinct though minute additional tooth. S. lateralis Koch. 
27. Anterior bend of flagellum overlying the tooth preceding the long 
interval, the shaft terminating a little posterior to the hind margin of the 
basal enlargement. Three distal teeth in the upper jaw, the second and third 
being of moderate size. S. erythronotoides sp. nov. 
28. Anterior bend more posteriorly situated, overlying the toothless 
interval: shaft reaching back about half way along the mandible. Basal 
enlargement high. Two distal teeth of upper jaw moderately well developed. 
S. erythronota Kraepelin. 
B. Shaft of flagellum not simply filiform, but more or less 
flattened and expanded in the distal portion, where the edges are 
frayed out into processes or deeply serrated. 
29. Terminal fang of upper jaw with a dorsal tooth but no keel or only a 
very weak one on its mesial side. Flagellum broad at the anterior bend, 
which overlies the tooth preceding the long interval, reaching back about as 
far as the ocular tubercle, and filiform over the greater portion of its length, 
but in the terminal third it expands slightly into a lamina and divides into 
two main portions, the longer one being drawn out to a filament with serrated 
margins, the shorter one ending abruptly but bearing a short and slender 
serrated extension running parallel to the longer process just mentioned. Two 
distal teeth of upper jaw moderately large. S. maraisi Hewitt. 
30. Anterior bend of flagellum overlying the toothless interval, the shaft 
reaching back beyond the middle of the mandible, being deeply and finely 
serrated along its upper edge in the distal half which is much flattened from 
the sides. Fang of upper jaw with an exceptionally high keel arising from the 
upper surface along its inner edge, just above the distal group of teeth and in 
front of the flagellum. S. spectralis Purcell. 
31. Anterior bend situated as in spectralis , the shaft short, about as long 
as the terminal fang of the lower jaw, and serrated along three edges in its 
distal half which is expanded except towards the apex. A thin upright blade- 
like keel, serrated anteriorly, and provided with a sharp forwardly directed 
tooth about the midde of its length, occurs on the inner side of the fang of 
the upper jaw. 5 . vincta Koch. 
C. Terminal fang of upper jaw grooved on its mesial side 
superiorly for the reception of the procurrent portion of the shaft 
of the flagellum, the groove continued in front of the anterior bend, 
being bounded mesially by a long keel which extends from the 
anterior bend towards the tip of the fang. Flagellum not broad at 
the anterior bend, the shaft filiform, not expanded. 
a. Anterior bend of flagellum posteriorly situated, over- 
lying some portion of the toothless interval. 
4 
