THE SMALLEST OF THE CENTURY PLAXTS 15 



the horny margined group. It need, therefore, be little more surprising 

 if Agave pumila of the latter group is found to be really at home in the 

 Andes, than that another littaea type should be found in the same exile, 

 though relatives of the latter are characteristic of southern ^Mexico 

 while known marginate specie? are more northern. 



