half the size of the posterior, between which a central occipital.
The posterior occipitals are fringed by some smaller marginal
scutes. Two large supraoculars on each side. Seven or eight
narrow upper labials, of which the penultimate is the largest.
Four chin-shields on one side, five on the other. Temporal
scales small, strongly keeled.
Ear very open, vertically long. Collar more distinct in
front of the shoulder-joint, and nearly obsolete across the
chest. Dorsal scales in eight, ventral in ten, longitudinal
series. Praeanal region covered by keeled scales, in size
and shape scarcely differing from those preceding them.
About twelve femoral pores. All the caudal scales strongly
keeled.
The fore limb pressed backwards does not reach the groin ;
the hind limb carried forwards extends to the ear. Thigh
finely granular behind.
The upper parts are brown, or, after the removal of the
epidermis, green iridescent. Back, anteriorly with a black
longitudinal band of each side of the median line, the two
bands coalescent further behind. An indistinct greenish band
along each side of the neck. Lower parts whitish.
millim.
Distance ot snout from v e n t .................................. 45
Length of t a i l ......................................................... n o
Distance of snout front ear . . . . . . . . 12
Length of fore l i m b ........................................... 20
Length of hind l im b .................................... 30
Length of fourth toe (measured from its junction
with the f i f t h ) ........................................ 12
I have given a full description of this lizard, as the specimen
found by Miss Kingsley at Lambarene seems to be only
the second known to exist in collections. Its specific identity
with Tachydromus Fordii of Hallowell might be questioned,
as this author has described the specimen in the museum of
the Philadelphia Academy as possessing only six rows of
ventral scales ; also the scutellation of the praeanal region is
differently described. However, as there is a great agreement
in other respects between the two specimens, and the locality
(Gaboon) as given by Hallowell points likewise to a specific
identity, I adopt the name given by the latter author.
Dipsadoboa assimilis.
Dipsadoboa assimilis, Matschie, SB. Ges. naturf. Fr. Berl. 1893, p. 173
(Togoland); Bocage, Jorn. Sc. Lish. iv. 1895, p. 17.
The specimen obtained at Lambarene agrees better with
D. assimilis than with D. unicolor with regard to the number
and disposition of the labial shields.
Professor Bocage refers his specimens from Fernando Po
also to D. assimilis, whilst, singularly enough, I have now
some evidence that the type of D. unicolor came from the
same island, as I received some years ago a specimen from
Fernando Po which is identical with D. unicolor. Therefore,
as far as our present experience goes, both D. unicolor
and assimilis (if they are really distinct) would seem to occur
in Fernando Po, while the former does not extend on to the
mainland.
Atheris anisolepis.
Atheris anisolepis, Mocquard, Bull. Soc. Philom. 1887, p. 90.
Atheris laviceps, Boettger, Zool. Anz. x. p. 651 ; Ber. Senckenb, Ges.
1888, p. 92, tab. ii. fig. 7 (head).
An adult specimen from Lambarene. The specimens from
which Boettger took his description came from Banana (Congo
delta). The principal distinctive characters of this species
are, in my opinion, the number and size of scales and the
two series of suboculars, rather than the degree of carination
of some of the scales on the crown of the head, which depends
on age.
Thanks to the kindness of Professor L. Vaillant and Dr.
Jentink I have been able, by a re-examination of the typical
specimens described by Schlegel and Mocquard, to form a
definite opinion as to the species of Atheris which deserve
recognition. They are the following :-A>
1. A. squamigera, Hallowell, = A . subocularis, Fisch., prob-
. ably = A. Burtonii, Gthr. With 17. (in A . Burtonii
with 19) series of scales; only one row of minute
subocular scales (exceptionally partly confluent with
upper labials).
2. A . anisolepis, Mocquard 1887), = A. Iceviceps, Boettger
(1887), — A . chloroechis, Boettg., part. With 22-25
series of scales ; two rows of minute suboculars, the
lower row sometimes incomplete, but always indicated
by several scales.