x PREFACE. 



My friend and former colleague, Mr. G. B. Howes, 

 rendered me much assistance in preparing and correcting 

 those parts of the directions which were drawn up in 

 England, and has also given considerable aid to my brother 

 in working out some doubtful points which arose while the 

 work was passing through the press. 



I am further indebted to Mr. Howes for the drawing 

 for Fig. 34, and to my brother for Fig. 32. Figs. 35, 36, 

 and 37 are copied from my father's monograph on the 

 Lizard's skull (Phil. Trans. 1879), and Fig. 38 from 

 Herpetologia Europ&a ; the remaining illustrations are from 

 my own drawings. The whole of them have been drawn on 

 the wood by Mr. Coombs, and engraved by Mr. Cooper : 

 judging from the few proofs which have so far reached 

 me, I have every reason to be grateful to those gentlemen 

 for the care and skill with which their work has been 

 done. 



T. J. P. 



OTAGO UNIVERSITY MUSEUM, 

 DUNEDIN, N.Z. 



June, 1883. 



