race in central Guatemala. These probably indicate the 
centers of origin of these two cultivated races from varie- 
ties of the same species or from closely related species. 
The West Indian race, which may not have occurred in 
Mexico until recent times, seems to be more closely re- 
lated to the Guatemalan race than to the Mexican and 
probably arose somewhere in lowland Central America. 
Hybridization may have played some part in the develop- 
ment of these races and certainly has been important in 
the formation of the modern commercial varieties (8). 
(8, 21, 97*, 188, 152, 191, 194*, 219) 
P. Schiedeana is a distinct species ranging from south- 
ern Mexico to Panama, but it is rarely cultivated except 
near Orizaba, Mexico, where it is of considerable impor- 
tance (153). 
Phaseolus: Ayecote, bul, frijol, bean. 
The bean is one of the ancient American trinity, maize- 
bean-squash, and is nowhere more important than in 
Mexico. The genus is not as well known as its economic 
value merits. A recent Russian paper, which the present 
author has not seen, is cited by Carter (86). Several spe- 
cies of beans are cultivated in Mexico: 
P. acutifolius 4. Gray: Tepary. 
This species is less important in Mexico than it is in 
the southwestern United States, where its resistance to 
drought and heat give it a great advantage over P. vul- 
garis and where it has its center of diversity. The wild 
forms of the tepary bean occur from western Texas to 
Arizona and southward to Jalisco. The most probable 
center of origin for the cultivated plant is northwestern 
Mexico (36). It is now found in cultivation in Chiapas 
and Guatemala, but its antiquity in these regions is not 
known (36, 79*). 
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