736 CALIFORNIA ACADEMY OF SCIENCES. 



ilization and national prosperity. Immigrants are pour- 

 ing in from all sides, but with them come unhappily foreign 

 weeds and plants, and foreign animals, which are bound 

 to, in a few years, considerably change the aspect of the 

 fauna and flora of the country. In the vicinity of the 

 cities near the coast, or along the highways, we find every- 

 where foreign plants and animals well established, which 

 are driving the native ones further back. If we, therefore, 

 wish to learn the original aspect of Mexican animal and 

 plant life, before man begins to interfere too much, we 

 must commence our studies at once. In a few years it 

 will be too late, as much which is the most interesting now 

 will then have changed or been exterminated in the same 

 manner as in this and many other countries. But there 

 are besides other reasons why explorations in Mexico 

 have been considered desirable, one of these is that in 

 that country animal and vegetable life is a hundred times 

 richer and more luxuriant than with us, and the collec- 

 tions acquired are thus correspondingly large. Another 

 point of very great importance is, that explorations in 

 Mexico are comparatively very cheap, and with the very 

 limited means at our disposal we have been able to bring 

 together collections the size and value of which could not 

 have been duplicated in our own country in ten times the 

 time and with ten times the cost. It has then simply been 

 a question of the largest collections with the least possible 

 cost. 



Our last three expeditions have been greatly assisted 

 by the courtesy of the Mexican Government, which, 

 through its Ministro de Hacienda, Hon. Jose Y. Liman- 

 tour, has caused special facilities to be extended to us in 

 all places visited, without which, it is safe to say, our suc- 

 cess would have been correspondingly less, and been 

 difficult to achieve. The expedi,tion of 1894 ^^^ ^^^^ 



