The figures that accompany Arber’s statement are 
particularly interesting in illustrating the marked broad- 
ening of the sheath in Phalaris canariensis and the re- 
duction of the leaf blade to a mere point in Hhrharta. 
Arber also describes and illustrates a broadening and 
shortening of the leaf sheaths and a reduction in the lam- 
inae in Agropyron repens Beauv., resulting from injury 
by insects. And Hitchcock (19385) illustrates a number 
of species of grasses in which the sheath or sheaths im- 
mediately below the inflorescence have become shorter 
and broader and have largely lost their laminae. It is 
evident, therefore, that the development of the husks in 
maize is nothing more than an exaggerated form of a 
morphological development which is widely distributed 
in the Gramineae. 
In several recent papers (1946,1948) the senior author 
described the evolutionary steps which were thought to 
have occurred in maize during evolution under domesti- 
cation. In the light of the direct evidence now bearing 
on this point the views previously expressed are subject 
to possible modification. For example, it was assumed 
that wild maize bore mixed staminate and pistillate in- 
florescences terminally on lateral branches whose sheaths 
and laminae were essentially identical with those on the 
main stalk. Although this assumption has not yet been 
shown to be erroneous, another possibility is now appar- 
ent. It is quite possible that wild maize already had dis- 
tinct staminate and pistillate inflorescences, and that a 
shortening of the internodes immediately below the pis- 
tillate inflorescence had already occurred, giving rise to 
an involucre of leaf sheaths which surrounded the base 
of the ear but did not enclose it. There is no reason why 
a plant with such an inflorescence could not have existed 
in a wild state. There is, at least, no doubt that such a 
plant did exist in the early stages of domestication. 
[ 234 J 
