WEATHERWAX: MORPHOLOGY OF FLOWERS OF ZEA Mays 133 
give similar descriptions and call the silk a style. Only one dis- 
senting opinion has thus far been noted, and that in Wood’s (7) 
text-book, published about 1870. Here (p. 48) he figures the 
pistil of Zea and mentions its long, filamentous stigma. 
All evidences indicate that the silk is stigmatic, at least in a 
rudimentary way, even to its base. The hairs are most numerous 
near the tip but are to be found all along the organ. Crozier 
(8) has noted that silks that have been repeatedly cut off are 
still capable of being pollenized, showing that it is not the forked 
tip alone that is stigmatic. Of course the part of the silk that is 
protected by the husks does not, under ordinary conditions, 
become a germinating place for pollen, but continued growth is 
always exposing parts that were previously covered. How long 
this might continue is not limited by any visible structural dif- 
ference, and it is probable that pollen will germinate on any part 
of the silk. Even those who persistently call it a style admit that 
the silk catches the pollen grains and furnishes them a place to 
germinate, and this is by definition the function of a stigma. 
In cross section the silk has the shape of an asymmetrical 
figure eight (Fic. 8). This appearance is due to a longitudinal 
groove extending along both the adaxial and abaxial sides. The 
abaxial groove is deep and narrow, and the one on the adaxial 
side is broad and shallow (Fics. 6-8). Near the tip these 
two grooves unite, making the silk unequally two-pointed (Fic. 5). 
A strand of vascular tissue traverses each side of the silk and con- 
tinues into the tip after the silk divides. In distribution the hairs 
are limited to the edges and adaxial side (Fics. 6-8), being 
more numerous, as has been said, near the distal extremity 
of the silk. If the two stigmas of the typical grass flower should 
unite for almost: their entire length, the organ formed would be, 
except for relative length, not unlike a corn silk. It seems wholly 
consistent, therefore, to consider the corn silk a compound stigma. 
Just what course the pollen tube takes with reference to the 
Parts of the pistil is not definitely known, but growth of the tube 
Causes the stigma to dry up. Silks that have been protected from 
pollen may, however, as Crozier (8) has pointed out, remain 
fresh for many days and continue to grow in length. 
If the silk is to be considered a stigma, then the style is the 
