6o 
Annals of the Transvaal Museum 
portion, the whole structure being fairly regularly attenuated from the 
widened basal portion up to the apex. The first tooth of the upper jaw is 
much nearer to the second than to the tip of the fang. 
B. falcifera Kraepelin. 
6. Distal dorsal bristle very stout in its basal two-thirds, where the 
surface is rather strongly denticulated except near the base; then becoming 
attenuated rather suddenly, the apical third being slender, smooth and taper- 
ing to a fine point. Flagellum quite slender, being only slightly expanded at 
the base, and the distal half being practically uniform in breadth throughout. 
The first tooth of the upper jaw is as near to the second as to the tip of the 
fang. B. filicovnis Hewitt. 
B. Flagellum short, not or scarcely surpassing the end of the fang 
when directed forwards, the distal portion being expanded into a widely 
open capsule, more or less oval or pear-shaped in outline, and the basal 
portion forming a distinct narrow stalk of attachment. 
7. Distal portion of upper jaw with a long and straight upper margin, 
the first three teeth subequal in size, the third being followed by a faiily long 
straight interval, the fourth tooth being small. Distal dorsal bristle long and 
straight, minutely echinated m its distal half, which is as stout as the basal 
half. B. cvepidulifeva Purcell. 
8. Distal portion of upper jaw curved towards the apex; the single series 
is continuous and includes two strong pointed teeth distally, followed by two 
small teeth : between the more distal pointed tooth and the tip of the fang, is 
an inner blunt laminate tooth paired with an outer more conical tooth. 
Distal dorsal bristle undifferentiated. B. litoralis Purcell. 
9. Similar to crepidulifera, but the distal portion of the upper jaw is 
curved : the single series comprises two large distal teeth, a small third tooth, 
and a large fourth in a continuous series. B. clunigeva Kraepelin. 
C. Flagellum a more or less pear-shaped capsule, with a wide 
elongated opening over the distal half or two-thirds of its length, the 
basal funnel-shaped part narrowed but not definitely petiolate. 
10. Distal part of flagellum broad, densely covered with shaggy hairs. 
Outer wall of flagellum furnished with a strong well-marked yellow axis 
which terminates distally in a short sharp claw. Second abdominal segment 
inferiorly carrying two pairs of sickle-shaped fleshy hairs situated near the 
midline, e B. unguicovnis Purcell. 
11. Second abdominal segment inferiorly with two groups of three fleshy 
hairs near the midline. Flagellum without prickles or setae on its surface, 
although the distal edges are slightly frayed: the yellow thickened rib is 
very broad, and the amount of free membrane dorsal to it is much less than 
in unguicovnis. B. laticosta Hewitt. 
12. Flagellum without a longitudinal thickened rib. Between the first 
large tooth of the upper jaw and the tip of the fang, there is a small obtuse 
tooth (which is absent in unguicovnis ). B. tvicolov Hewitt. 
D. Flagellum like that of C, but widest about the middle of its length 
and gradually tapering distally to a slender apex. 
