INTRODUCTION. Vv 
purchased of M. Becker, may be generally regarded as au- 
thentically determined according to the Continental nomen- 
elature, for he accurately compares them with the different 
cabinets. 
To give an idea of the extent of the collection, it may be 
mentioned that M. Godart, in the last general work on Diur- 
nal Lepidoptera, published in the Encyclopédie Méthodique 
(vol. ix.), in 1819, described 1138 species of the families 
contained in this part of the list; while the Museum collec- 
tions consist of 1300 species: and several of M. Godart’s 
species have been regarded in this Catalogue as varieties or 
duplicate descriptions. 
JOHN EDWARD GRAY. 
British Museum, 
26th December, 1844. 
