HOWARD AND HOWARD. 17 
macaroni wheats have tall straws solid in the upper portion, the 
other two sub-species have hollow stems. The dwarf wheats, how- 
ever, have short, stiff and strong straws, while those of the common 
wheats are taller, thinner and on the whole weaker. No exceptions 
to the general rule, such as macaroni wheats with hollow stems and 
common wheats with solid straws, as mentioned by Koemicke,! 
have been noticed. 
(c) Length—The common wheats have straw intermediate 
in length between the tall stems of the macaroni wheats and the 
short straw of the dwarf wheats. There is considerable variation, 
however, in the length of straw between the various common 
wheats of the Indian plains. 
(d) Colour.—The colour of the straw may be white, yellow or 
pink. The pink colour is especially well-developed in some of the 
Punjab dwarf wheats (types 5 and 7) and in type 19, a common 
wheat. It is also seen in the two Bengal durum wheats but only in 
good years. After exposure to the sun or after long storage the 
colour fades to a dirty greyish tint. It is best seen in the field just 
before the crop is ripe. 
As regards the general straw characters, besides the main differ- 
ences in thesub-species, the numerous varieties of each sub-species 
show well-marked straw characters. In some the straw is tall and 
strong and not liable to lodge and the colour may be pink. Such 
straw characters, however, are difficult to determine, for the length 
of the straw as well as its strength depends to a very large extent 
on the nature of the soil, the nutrition andthe soil moisture. For- 
tunately, the character of the straw is not often needed as the sole 
means of distinguishing types, but if it has to be used, the wheats 
must be grown next to next in similar soil and under equal condi- 
tions in order that reliance can be placed on such characters. In 
studying the Punjab wheats, we have found it necessary in one case 
to separate two agricultural types mainly on their straw characters 
and also on earliness and lateness. In this case, however, the 
! Koernicke, |. c¢. 
