July 7 th, 1923 
My de r Dr. Standiey: 
Hare you ever 'been successful in 
locating the materials on which LaLave and Lexarza based 
their new genera and species of Mexican plants.?! may 
have put this same question to you before. I have arrived 
at a point where, unfortunately, the treatment of some four hun¬ 
dred species depends on definite knowledge of one of the 
genera proposed by Lexarsa. If we can disregard the LaLave 
and Lexarsa proposals because no types are extant, the* way 
is easy. But one must be sure of such a thing when a large 
number oaf species must be disposed of. 
Yours faithfully, 
