x INTRODUCTION. 
J. Wright, E'sq., as the illustrations of the species from Tro- 
pical and South America and the West Indies, described 
by Sir Hans Sloane, Browne, Wagler, Spix, Graven- 
horst, Guilding, and others. 
The specimens purchased or procured in exchange from 
The Leyden Museum, as the types of the species described 
and figured by Dr. Schlegel, in his Fauna of Japan 
and in his Abbildungen, and by Dr. 8. Muller, in his 
work on the Reptiles of New Guinea, Borneo, &c. 
The South African Museun, as the types of the species 
described by Dr. A. Smith, in his Illustrations of the 
Zoology of South Africa. 
M. Brandt’s Collection, as the types of the species described 
by Pallas, Eversmann, and other Russian naturalists. 
JOHN EDWARD GRAY. 
British Museum, 
October 1, 1849. 
