The British Guiana Museum. 221 
while this is a characteristic feature of the monkeys of 
the forest-clad South American region. 
In the next case are seen various dried and spirit 
specimens. Above are shewn, chiefly, collections of 
colonial Reptiles in spirit. Among them are speci- 
mens of the rattle-snake (Crotalus horridusj, the labarria 
(Trigonocephalies atroxj, the ringed boa (Epicrates 
cenchris), the yellow-tail (Spilotes corais) } together with 
various forms of coral snakes, whip snakes, water 
snakes and grass snakes, besides the land and 
water camoodies already mentioned. Among the lizards 
are seen species of Iguana^ a type in which, as in several 
other lizards, an extra single eye situated in the flesh 
direftly over the middle of the brain, and hence not 
capable of being used for sight, has been discovered : 
specimens of the marbled lizard (Polychrus marmoratus) 
a very harmless reptile, but commonly regarded as being 
poisonous, known as the gamma or colonial chameleon : a 
salempenta, with eggs and young, shewing their very 
varied coloration : a specimen of the gecko or wood- 
slave (Platydaftylus rapicauda) , a very curious and 
harmless type of lizard, commonly regarded as being 
poisonous ; in the geckos (so called on account of their 
cry) the toes are much flattened to form adhesive suckers, 
so that the animal is able to stick tightly to an obje6l in 
any position ; these lizards are rather rare, but are found 
under walls and houses and in dark situations — hence 
the eyes are much enlarged ; the tail, when broken 
away, is renewed, but then takes on a very different 
shape and often becomes somewhat like a turnip ; 
it might be mentioned in this connexion that there 
is but one known poisonous lizard (Heloderma) and 
FF 
