192 DR. H. GADOW ON MEXICAN [June 6, 
tours through many 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 number of native specimens in the Govern- 
mental Museums and other Institutions of various towns in 
Mexico; for instance, in Mexico City, Orizaba, and Oaxaca, but 
the labels vouchsafe at best no further trustworthy information 
than ‘“‘ Mexico” or “ La Republica.” 
6. Lastly, the material which I have collected myself, or noted 
down, during two journeys in Mexico, notably in the Valley of 
Mexico, the States of Vera Cruz, Oaxaca, Guerrero, Morelos, and 
Puebla, and in the neighbourhood 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 transits, quite enough, however, 
to gather the main aspects of this enormous stretch of country. 
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 Cation 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 erroneous on further 
reference to the original papers. 
Tt 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 
Giinther, 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 
