BUCEPHALUS VIRIDIS.
extremity, with a faint carina along its centre, the lateral ones oblong, each
with an obtuse angular or semilunar point, and a carina extending from the
base, and terminating on the upper edge of the scale before reaching its
apex ; the two scales of each row nearest to the abdominal plates broad and
subtriangular, the points rounded, and the longitudinal carina with which
each is marked terminates on its lower edge behind its point. The scales
on the tail are short, broad, distinctly imbricate, and somewhat five-sided,
characters which they retain to its extremity; abdominal plates, 181 ; sub-
caudal scales, 101 in each row.
Unless when the skin is distended, the scales of the transverse rows overlap
each other so much, that only the inner edge of each is left uncovered ; at such
times the scales appear linear.
DIMENSIONS.
Feet. Inches.
Length from the tip of the nose to-the extremity of the tail... 4 9
Length of the tail........................................................................ * *
Circumference of the thickest part of the body....................... 0 3
The only specimen of this species which we obtained was found near to Old Latakoo, and at
the time of its discovery was in a half torpid state, and coiled up among some dry grass which
was interweaved with the slender branches of a small shrub. According to the natives, it
ascends trees to rob the nests of birds, and its occurrence is by no means rare in that country
during the summer season. Although a celebrated Herpetologist has expressed his belief* that
snakes with the general characters of the species just described, ought to be retained in his
genus DendropkiSj yet it appears to me that their position in-it would be equally inappropriate,
as it would be in the restricted genus Coluber. Besides the species now described, there are at
least four others inhabiting South Africa ; and though they have been regarded by the author
just alluded to as only varieties of one species, nevertheless, I am more convinced at present
than when I submitted descriptions of them to the public/f that each ought to be regarded as
distinct from the others. Supposing Bucephalus typicus, Bellii, gutturalis and Jardinii, to
be only varieties of one species, how are we to explain the circumstances of their being all
found in a similar climate and in similar descriptions of country, yet, nevertheless, in very
different localities, and each propagating individuals like itself, which as far as we know never
vary. In proportion as our knowledge of the more intricate details in the scheme of nature
becomes extended, it will probably be discovered that each genus is regulated to a certain
extent upon a plan peculiar to itself, and that in some genera the distribution of colours, not
less than the peculiar tints, will furnish excellent specific distinctions. As regards Bucephalus,
I feel disposed to consider it one of such genera.
* Physionomie des Serpens par H. Schlegel, page 238. Hague, 1837.
t Zoological Journal, Vol. iv. page 441, May 1829.