192 DR. H. GADOw ON MEXICAN [June 6, 



tours through mauy States of Mexico. These, and others, I have 

 been able to examine owing to the courtesy of the officials of the 

 Field Columbia Museum, Chicago. Dr. Meek has, moreover, 

 given me much verbal information about the physical aspects 

 of the places visited by him. 



5. There is a fair numbei' of native specimens in the Govern- 

 mental Musemns and other Institutions of various towns in 

 Mexico ; foi- instance, in Mexico City, Orizaba, and Oaxaca, but 

 the labels vouchsafe at best no further trustworthy information 

 than " Mexico " or " La Repitblica." 



6. Lastly, the material which I have collected myself, or noted 

 down, during two journeys in Mexico, notably in the Valley of 

 M^exico, the States of Vera Cruz, Oaxaca, Guerrero, Morelos, and 

 Puebla, and in the neighboui-hood of Zapotlan s. Guzman in 

 Jalisco, especially the Nevado de Colima. The features of the 

 Central and Northern plateau, except the vicinity of El Paso, 

 I know only from several rapid tiunsits, quite enough, howevei-, 

 to gather the main aspects of this enormous stretch of countiy. 

 Moreover, here Dr. Meek's information has been especially 

 welcome. Valuable for comparison, but of too short a time 

 for serious collecting, were a few days passed in New Mexico, 

 the Grand Canon of Arizona, the Californian Desert, and the 

 neighbourhood of San Francisco. 



A few words are necessary as to the way in which I have 

 marshalled the thousands of data. The reputed localities were 

 marked down on an outlined map of the Republic, a separate 

 map for each species. In this way alone generalisations could be 

 formed, often at a glance, concerning the distribution of the 

 species and genera. Many localities, at first suspicious, revealed 

 themselves as very doubtful or as obviously eironeous on further 

 reference to the original papers. 



It was also found that the number of different localities is 

 astonishingly small, less than 100, although they now cover a 

 fair portion of the whole country. With the exception of 20, all 

 these localities lie south of the line Guadalajara, Guanajuato, 

 Tampico. The whole State of Michoacan and the western half 

 of Guerrero are still an almost absolute terra incognita, but to 

 judge from what I have found in Middle Guerrero and what is 

 known from Colima, the fauna seems to be rather continuous. 

 However, the basin of the Lower Balsas and thence to Colima 

 will in all probability yield much of interest to whoever will brave 

 these inhospitable and positively unknown regions. 



Both Godman (introduction to the volume on Rhopalocera) and 

 GUnther, in their statistical tables, have divided Mexico simply 

 into Northern and Southern by an absolutely arbitrary line which 

 runs from Mazatlan to Tampico right across the country ! They 

 have done this in spite of their correct statements about the 

 main physical features of Mexico, the unmistakable continuation 

 of North American forms over the Plateau, and the extension of 



