Zoolofjica I Miscellany . 
41 
Synopsis of the species of prehensile-tailed Snakes, or 
Family Boid^. Bj J. E. Gray, F.R.S., &c. 
Fam. BOIDJD. — Tlie ventral sMeMs narrow, transverse, band-like, 
often six-sided; the hinder limbs developed under the skin, formed of 
several bones and generally ending in an exserted horny spur, placed one 
on each side of the vent. Tail short, prehensile. The pupil oblong, 
erect. — Killing their prey by pressure. 
This family contains 20 genera and 32 species: of these 8 genera and 
10 species are confined to Tropical America; 4 genera and 5 species are 
found in Africa; 6 genera and 8 species are found in Asia; 4 genera and 
8 species are found in New Holland; and 1 species is found in Europe. 
The species of the genus Python are found both in Africa and Asia, but each 
species has its peculiar country ; one species of Eryx is common to the 
South of Europe and North Africa. Schlegel described 19 species; of 
those here described 25 species are from the British Museum collection, 1 
from the Museum of the Edinburgh University, 2 from the Leyden Muse- 
um, and 4 from the Paris collection ; the latter is chiefly known to me 
through the works of Schlegel. 
I. The rudimentary hinder limbs ending in distinct horny spurs, exposed on 
the side of the vent. Eyes nocturnal ; pupil oblong, erect. 
A. Head elongate, distinct, muzzle truncated. Tail strongly prehensile. 
a. Subcaudal plates entire ; scales smooth. America. Boina. 
They live in marshy places in South America; fixing themselves by the 
tail to some aquatic tree, they allow their bodies to float, and thus entrap 
the animals which come to drink. The spurs were first noticed by Dr. P. 
Browne. (Hist. Jam. 1789, 461). 
I. Boa. Body fusiform: muzzle scaly in front: labial shields not pitted, 
short, narrow : eyes surrounded with small scales. 
I. Boa constrictor, Linn. Mus. Adolph, i. 1. 17, fig. 3. B. oropliryas, and 
B. ophryas, Linn. 
Tropical America. Brit Mus. 
II. Eunectes, Wagl. Body fusiform : muzzle shielded, labial shields 
not pitted, the front ones high and narrow, hinder lower two-rowed : loreal 
shields two, front small, hinder large : eyes with small shields above and 
behind, and a large ocular in front : superciliary plate distinct. 
1. Eunectes murina. Boa murina, Linn. Boa Scytale, Linn. B. ana- 
conda, Baud. B. aquatica, Niewied. B. gigas, Latr. 
Inhabits Brazils. Brit. Mus. There is a specimen 20 feet long in the 
Berlin Museum ; the unhatched young in the British Museum are 2 feet 
long. 
GRAY, ZOOL. MISC.— MARCH, 1842 . F 
