SNAKES. 285 
The Rhomb-marked Snake (Psammophylax rhombeatus) is a 
native of South Africa, and should be kept while in this country, 
except during the hottest months of the year, under the influence 
of artificial heat. Its food ought to consist of mice and rats. It 
is hardy and easily tamed. It may sometimes be bought for 
about 10s. 
P. rhombeatus has a head with a flat crown, and distinct from 
the neck; an eye of moderate size, having a round pupil; a 
rostral which is carried backwards between the anterior frontals ; 
one pre-ocular, two post-oculars, one loreal, and narrow ovate 
scales, arranged in seventeen or nineteen rows. The upper parts 
of the body are a greyish or yellowish-brown, marked with three 
or four rows of rhomboidal dark black-edged spots. 
The All-green Tree Snake (Philodryas viridissimus), a most 
beautiful and active creature, is a native of South America. Its 
food should consist of small frogs (it prefers tree-frogs) and young, 
hairless mice. Its artificially-heated case ought to be provided 
with some retreat, such as an orange-tree or a fuchsia, in which, 
owing to its clever coiling and the colouring of its body, it will 
be able to hide itself, or, at any rate, to escape the notice of 
the unobservant. 
P. viridissimus has a very slender body and tail, which are 
coloured uniformly green, a conical head and a moderately-sized 
eye, a rather elongated loreal, and smooth scales placed in 
nineteen rows. 
The Cross-marked Snake (Psammophis crucifer) is an interesting 
and fairly hardy little animal. It is a member of a family of 
_ Bush Snakes (Psammophide), and a native of South Africa. Its 
food should consist of frogs, and it ought to be kept in an artifi- 
cially-heated Vivarium. . 
P. crucifer has a slender body and tail, a groove before the eye, 
the pupil of which is round, a pointed snout, a long loreal, one 
pree-ocular, and two post-oculars. The scales are long and smooth. 
The upper parts are olive, and there is a black-edged streak 
running from the snout to the end of the tail. A transverse 
band formsa cross on the nape of the neck. 
The Hissing Sand Snake (Psammophis stbilans) is also a native 
of South Africa. It may be fed upon birds and mice. Like its 
