eight-rowed. These are pretty obviously cobs of Harin- 
oso de Ocho, or something very much like it. The third 
group, comprising nine cobs, is intermediate between 
these. The cobs represent Harinoso de Ocho, only 
slightly modified by the introgression of other elements. 
They may be similar to the present-day ‘‘Maiz Blando 
de Sonora,” described by Wellhausen et a/ (1952), which, 
in turn, has some similarity to the Pima-Papago corn of 
southern Arizona. 
There are twelve unclassified fragments from this level. 
No cobs which could be clearly assigned to Chapalote 
are found in this surface level. Apparently, this primi- 
tive race was almost completely replaced by Harinoso 
de Ocho and the modern race evolving from the amalga- 
mation through hybridization of earlier races. 
Slab Cave 
Trench 2 (0-12"). Five intact cobs, 6.5, 7.5, 7.5, 10, 
and 9 cm. in length. The first four appear to be cobs 
of a short-eared form of Chapalote. The last resembles 
Harinoso de Ocho. Three additional intact cobs, 5.5, 
5.5, and 6 cm. in length, are Tripsacoid with indurated 
glumes and rachises and a slight tendency towards sup- 
pression of one member of a pair of spikelets. ‘wo frag- 
ments are also Tripsacoid. 
The remaining fragments can be separated into three 
more or less distinct groups. The first, comprising eleven 
specimens, shows some resemblance to cobs of Chapa- 
lote. The second group, nine specimens, are related to 
Harinoso de Ocho; and the third group, also nine speci- 
mens, are similar to the most recent maize from Swallow 
Cave, which, as already mentioned, is similar to the 
modern Cristalino de Chihuahua. 
The collection from this test trench includes 82 well- 
preserved kernels, of which fifteen have brown pericarp. 
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