82 THE SNAKES OF SOUTH AFRICA. 
7. GENUS PRosyMNA.—Scales smooth, in 15 or 17 rows. Pupil vertically 
elliptic ; rostral very large, with angular horizontal edge; pos- 
terior maxillary teeth strongly enlarged. Maxillary bone short 
with 7 or 8 teeth. 
8. GENUS HomALosoma.—Scales smooth in 15 rows. Pupil round; 
rostral small; nasal single; anterior maxillary teeth longest. 
Maxillary short, with ro to 12 teeth. Tail short, sub-caudals in 
two rows. 
9g. GENUS CHLOROPHIS.—Scales smooth with apical pits in 15 rows. 
Tail long (sub-caudals more than 80 pairs) ; pupil round ; posterior 
maxillary teeth longest. Sub-caudals not keeled, and in 2 rows. 
10. GENUS PHILOTHAMNUS.—Scales smooth with apical pits, in 13 or 15 
rows, disposed obliquely, at least on the anterior part of the body. 
Sub-caudals keeled and notched, like the ventrals. Tail long. 
II. GENUS SIMOCEPHALUS.—Scales keeled, without pits, in 15 or 17 rows ; 
those of the vertebral row enlarged and bi-carinate; anterior 
maxillary teeth longest. Pupil vertically elliptic. 
12. GENUS DasyPELTIS.—Scales in 23 to 27 rows, laterals very oblique, 
and with serrated keels; teeth very small and few. Pupil 
vertically elliptic. 
Genus TROPIDONOTUS. 
Two Species in South Africa. 
KEY SO HE SPE ChES: 
Ventrals 162-180 ; anal entire .. SC .. Lvopidonotus levissimus. 
Ventrals 131-149 ; anal divided 50 .. Lvopidonotus olivaceous. 
I. TROPIDONOTUS L&viIssimMuS. Watermeyer’s Black Snake. 
Synonyms—Natrix levissimus ; Grayia lubrica. 
Colour—Dark shining black above, a narrow yellow line on either side 
of the head behind the eye; below, yellow, with a narrow ill- 
defined dark line running the whole length of the body along 
the centre of the ventrals. The two outer rows of scales spotted 
and blotched with black. 
Average length—3 feet. 
Distribution—Eastern Province, Cape Colony; Natal. 
2. TROPIDONOTUS OLIVACEOUS. Banded Olive Snake. Olyfen Slang. 
Synonym—Coronella olivacea. 
Colour—Olive or brown above, with a more or less distinct darker 
vertebral band 4 or 5 scales wide, bordered on each side by a 
series of whitish dots; flanks and ends of ventrals olive ; upper 
lip yellowish, the sutures between the shields black; ventrals 
yellowish, sometimes edged with olive. 
Average length—2 feet. 
Distribution—Southern Rhodesia ; North to Tropical Africa. 
Genus ABLABOPHIS. 
One Species in South Africa. 
Scales smooth with apical pits, in I9 rows. 
Frontal at least once and a half as long as 
broad; maxillary teeth equal .. a .. Ablabophis rufulus. 
