IV PREFACE. 



Wagler's frame was strong and vigorous; he was 

 devoted to field-sports for the opportunities they gave 

 him of observing Nature, and was an excellent shot. 

 On the 15th of August, 1832, as he was returning 

 from one of his hunting-expeditions near Munich, he 

 received a severe wound from the accidental discharge 

 of a gun, which, in spite of every attention, caused his 

 death on the 2Srd of the same month, at the early age 

 of 32 years. 



Wagler worked principally on Reptiles, Amphibians, 

 and Birds, and, as regards the two former classes, will 

 ever be known as the author of the volume devoted to 

 the Serpents in Spix^s great work on the Zoology of 

 Brazil and of his own ' Descriptiones et Icones Amphi- 

 biorum ' and ' Natiirliches System der Amphibien/ 

 His two principal ornithological works were a Mono- 

 graph of the Psittacidse, published in the 'Trans- 

 actions of the E:)yal Academy of Munich' (1832), and 

 his ' Systema Avium,' unfortunately left incomplete. 



Besides these, the six Essays which he contributed, 

 in 1829 and the three following years, to the pages of 

 Oken's 'Isis' are constantly referred to by ornitho- 

 logists, whose studies will, we trust, be facilitated by 

 the present reprint of them, which, except for the cor- 

 rection of a few very obvious misprints, has been made 

 word for word from the original. 



P. L. S. 



11 Hanover Square, London, 

 Jan. 5th, 1884. 



