CONTRIBUTIONS TO WESTERN BOTANY NO. 16 



They surely must be immigrants, brought in along the trails by Mexican 

 tiavelers, but the reason why they persist is that they all belong to the same 

 life zone, the Tropical, which prevails throughout to the very northern limits. 

 We find the papaya growing as luxuriously at San Jose del Cabo as in 

 Oaxaca. We find the cocoanut growing all along the coasts. We find the 

 devil grass as abundant in one region as another, and as much of a curse. 



"ore we are sure our plants 



ttempting to identify plants we have to comb the entir 

 re sure our plants are new. The flora of the republic i 

 North America. To me the theory of Willis has bee] 



known, and was long before he was born, but never made 



much of becaus differently to its 



environment according to its inherent vitality, its adaptability, and means of 

 transportation. The scattering occurrence of many species is evidently a 



evidence of tbeir recent creation. There are more of these in Mexico than any 

 < niter region that I know, -it is to be expected. There 



is no evidence of forced mi ; aes) as is the case in the 



fiMted States and Canada. On the other hand human agencies hav been 

 active for half a millenium, but only by the transportation of animals and 



CRITICISM. 



a recent i-sue of the American Botanist, the editor i 

 iriiMitious So. 15 says, as he turns its pages, he 

 xt. I am sorry that he has a guilty conscience. '. 

 , for I don't know anything about his magazine, bu 



tors are cowardly pussyfoots, and there is no anim 



BOTANISTS WHOM I HAVE KNOWN. 



C. G. Pringle. My acquaintance with Pringle began by correspondence 



Kvhnens. Pringle impressed me as a painstaking botanist from the first, 

 id one specially acquainted with the ferns. His specimens always were 

 ry fine. I remember getting material of Astragalus Robbinsii from Smug- 

 er's Notch (the type locality) from him. He was also well versed in Carcx. 

 i those days very few botanists bothered with Carex or the grasses. After 

 cli year's work in the west he would write me asking for more material, 

 id he always had enough to exchange, winding up with a lot of ferns from 

 ■ H kwaiian islands. Along toward the last he wrote me asking what I 

 ought of his coming west and botanizing in Mexico. My reply was that 

 better keep out. Then in the spring of 1882 I was at San Diego and 

 irry told me that he had just arrived, and he suggested that we form a 

 rly and go to Envenada together, which we did. ( >n that trip I saw much 



