53 
the heads had begun to put forth. Though not so eaily in ripen- 
ing, the appearance of these two patches at harvest, indicated, so 
far as a single experiment could do, that wheat might be mowed 
at the former period without any diminution of its productiveness, 
whilst at the latter, both the straw and heads would be of a more 
slender and feeble growth. 
6. Fly proof wheats.—That there are any kinds of wheat which 
are perfectly “ fly proof,” (to use a common and expressive term, ) 
as has been sometimes stated, we wholly disbelieve. At times 
when the fly is so excessively numerous as to attack barley and 
rye, it is not probable that any of the cultivated species of the 
genus Triticum can entirely withstand its attacks. But that there 
are kinds of this grain, that escape with little injury, when other 
kinds are almost wholly destroyed, is a well established fact. 
What the peculiar properties possessed by these varieties are, that 
render them thus singularly invulnerable, has never been investi- 
gated with that degree of accuracy which so interesting and im- 
portant a subject well merits. Mr. Worth supposes that fly proof 
wheats must have smooth leaves, affording no grooved or chan- 
neled surface to hold the eggs of the fly. (Amer. Far., ii., 181.) 
Mr. Smeltzer thinks the leaves of such wheat stand out horizon- 
tally from the stem, or incline downwards, instead of being erect, 
and that the egg is thus washed to the ground by rains. (Patent 
Off. Report, 1844, p. 434.) The Hon. J. Taliaferro regards the 
immunity as proceeding from the strength and vigor of the roots, 
whereby the plant continues to grow, notwithstanding the ex- 
haustion of its juices by the worm. (Patent Off. Report, 1842, 
App. No. 1.) This theory appears to us more plausible and more 
in accordance with the facts recorded with regard to these varie- 
ties, than any other which has been proposed. Other opinions 
less specific, might be alluded to, but all of them are opinions 
merely, as we discover no evidence of their having been substan- 
tiated by a diligent investigation of this point. The reputation 
of the Unperuiit wear has already been sufficiently shown. This 
was a bearded white-chaff, with a plump yellow berry, requiring 
to be thoroughly dried before grinding, and then producing flour 
