the central spike is as much in need of explanation as 
the ear. 
Hypotheses Regarding the Ear of Maize 
There have been three general hypotheses regarding 
the ear of maize: (1) That it is the product of the fusion 
of two or more distichous (two-ranked) spikes. (2) That 
it originated from the shortening and twisting of a dis- 
tichous spike. (8) That it is the result of the transforma- 
tion of a panicle to a spike through the reduction of 
branches. 
The Fusion Hypothesis. It is not surprising that 
botanists familiar with the compound nature of many 
fruits should, when confronted with an ear of maize, 
think immediately in terms of fusion. And when 
branched ears, ears apparently ‘‘disrupted’’ into their 
component parts, are encountered, the fusion hypothesis 
becomes almost inevitable. Little wonder that this hy- 
pothesis is the oldest of the three and has been, by all 
odds, the most popular. Ascherson, Hackel, Harsh- 
berger, Gernert, Wordsell, and Goebel * have all inter- 
preted the ear of maize as arising through the fusion of 
two-ranked spikes either like those of teosinte or Tripsa- 
cum, or like the lateral branches of the maize tassel. 
The serious weakness of the fusion hypothesis, so far as 
maize is concerned, is that there is no concrete evidence 
in support of it and considerable evidence in conflict with 
it. Branched ears, bifurcated or many-branched at the 
tip or bearing branches at the base, have repeatedly been 
regarded as evidence for the compound nature of the 
maize ear. But the majority of these branched ears prove 
upon examination to represent a type of branching which 
* Cf, Weatherwax (19) or Mangelsdorf and Reeves (18) for refer- 
ences. 
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