11 



I freely acknowledge my indebtedness to the books of Dr. Nicholson and 

 Major Wall, and advise anyone who wishes to pursue the subject a little 

 further to get them, especially the latter. 



I have also consulted Mr, Boulenger's Catalogue of Snakes in the 

 British Museum, and am indebted to Captain H. W. Acton, I.MS., for 



many useful hints. 



My thanks are due to Captain D. G. Cooper, I.M.S., for drawing the 



diagrams. 



