WEATHERWAX: THE EVOLUTION OF MAIZE 321 
ment of any part of the plant. As a typical instance of mis- 
interpretation of its structure may be cited a statement in a 
recent textbook (2, p. 137), where it is spoken of as being made 
up of kernels fastened end to 
end, the whole structure hav- 
ing nothing to correspond to 
the cob in maize. Collins’s 
description: (9, p. 525) of the 
spike as ‘one-rowed”’ is 
equally misleading. 
This spike is made up of ¢---- 
two rows of functional spike- 
lets borne alternately in alve- 
structure (F1GS. 27, 28) which 
represents the other. spikelet 
of the pair. Structurally, 
then, the spike has four rows 
25 
of spikelets It will be re- Fic. 25. An “ear” of teosinte, covered 
h : h | by its single husk, which has a rudimentary 
membered that in the male lamina, L. Fic. 26. Portion of a stem of 
spike the pedicelled spikelets  teosinte bearing a cluster of female spikes, 
are symmetrically arranged 
on the rachis, with the sessile ones below them; but, in the 
female spike, the fully developed sessile spikelets occupy the 
symmetrical positions, and the rudimentary pedicelled ones have 
been crowded up to a dorsal position (Fics. 34, 35). In 
teosinte somewhat mixed with maize the rudimentary spikelet 
is sometimes replaced with a sterile or male, pedicelled one, and a 
little further contamination with maize produces two functional 
female spikelets side by side. Paired female spikelets are also 
occasionally found in pure teosinte. These facts indicate that 
the female spike is the homologue of one of the branches of the 
tassel, and it probably does not morphologically terminate the 
shoot of which it is a part. 
The female spikelet consists of the same parts as that in maize. _ 
The lower flower is aborted, rudimentary stamens are present, 
