$2 REPTILES AND BIRDS. 
It is a remarkable fact that the poison is secreted after death. 
Dr. Bell, in his “ History of British Reptiles,” adduces the following 
as evidence of the facts:—He was dissecting very carefully and 
minutely the poison glands of a large rattlesnake, which had been 
dead some hours ; the head had been taken off immediately after 
death ; yet, as Dr. Bell continued his dissection, the poison con- 
tinued to be secreted so fast as to require to be dried up occasionally 
with a sponge or rag: and his belief is, that there could not be less 
than six or eight drops of the poison. It is obvious that such 
experiments require the utmost caution, seeing that preserved speci- 
mens are not without danger. 
[The family of the Vperide, or true Vipers, are peculiar to the 
Old World, inclusive of Australia, with the sole known exception of 
one species in Peru. They have generally a robust body, with non- 
prehensile tail; the head broad or thick, generally scaly above or 
incompletely shielded ; the eye of moderate size, with vertical pupil, 
and they are at once distinguished from the Crofaiid@ by the absence 
of the pit below the eye. ‘The scales are keeled except in one genus 
(Acanthopis). For the most part, these reptiles inhabit exposed and 
arid situations, though perhaps all of them will take to the water on 
occasions, as does the common British Adder. 
They are divided, firstly, into those which have a depressed head,« 
rounded on the sides, and covered with acutely-keeled scales. Some 
of these have large nostrils in the centre of a ring-like shield, edged 
with a large scale above. Such are the genera Dadoia in the warmer 
parts of Asia, and C/o¢ho, which is peculiar to Africa—both pepens 
are extremely venomous. 
The famous Zic-folonga of Ceylon (Dadota elegans) is also widely 
diffused over India and Burmah. It is beautifully marked with three 
rows of white-edged, oblong, brown spots. Occasionally the spots 
forming the middle row are “connected like the beads of a necklace, 
whence the name Cobra monil (literally Coluber moniliger), applied to 
the young of this Viper by the Indo-Portuguese, and now corrupted 
into ‘cobra de manilla,” which bears the reputation of being a highly 
poisonous Snake of diminutive size ; it attains, however, to a length 
of nearly five feet, the tail then measuring about eight inches, with 
considerable thickness of body. It is nocturnal, and preys chiefly 
on mice. In Burmah this formidable Viper is dreaded almost as 
much as the Hamadryas. It has been obtained in the Himalayas at 
an elevation of 5,500 feet, at Almorah, and elsewhere. Mr. Theobald 
has known one to kill a bull-terrier in twenty minutes. The D. 
xanthina is a second species of this form inhabiting Asia Minor, 
