132 Brenchley. — On the Strength and Development of 
of the surrounding carbohydrates. At first the dense nuclei become some- 
what deformed, as the neighbouring starch grains begin to press upon them, 
making dents in the nuclear matter. As the pressure from without increases 
the substance of the nucleus is squeezed out between the starch grains, 
eventually surrounding and enclosing them. The method of procedure 
might be illustrated by taking small balls of putty and pushing peas into 
them. A section across such a ball would resemble the ‘ network J nuclei 
of the wheat grain — if only a few peas were present, the putty would appear 
as a thick-walled network, while if the peas were in contact the matrix of 
putty would be well spread out into quite a fine reticulum, filling up the 
interspaces between the intruding bodies. 
This later stage in nuclear disorganization follows the same course 
as the initial stage and spreads outwards and downwards, though many 
of the nuclei in the sub-aleuronic layer never get so far, simply losing 
their nucleoli and becoming dense, but not being subjected to the 
intrusion of starch grains. The nuclei which are furthest advanced in 
disorganization, showing an exceedingly attenuated reticulum, do not stain 
at all well, and need careful observation in some cases if they are not to be 
overlooked. 
This disorganization is by no means completed by the time the corn is 
cut, but continues its progress while it is standing in ‘ stook 5 previous to 
carrying. The Square Head’s Master from Plot 3, Broadbalk, was cut on 
August 5, 1904, and carted on August 12. On the former date nuclear 
networks had spread as far downwards as the base of the embryo, below 
which solid nuclei still persisted. Seven days later, when carted, networks 
could be found right through the grain from top to bottom. Generally 
speaking, at this late stage in maturation the endosperm cells at the tip of 
the grain contained nuclei in only the very finest network stage ; towards 
the lower end of the kernel, the networks occurred chiefly in the middle 
of the flanks and were coarser, while at this level the nuclei in the sub- 
aleuronic layers still remained in most cases dense and solid. These latter 
changes are evidently due to desiccation, which the analyses show to be 
a marked feature of the last stages of ripening, especially after the corn is 
cut, and not to the further influx of reserve food material. Two other 
varieties of wheat were examined with similar results, but in no case was 
such disorganization seen in any cells of the aleurone layer. 
There is just a possibility that these facts may have some bearing on 
the problem of the vitality of the endosperm tissue, corroborating from the 
cytological standpoint some of the recent work on the subject. Miss 
Bruschi ( 15 ), fully admitting the vitality of the aleurone layer, maintains 
that only the immediately sub-aleuronic cells can be regarded as in any 
sense living, all the rest of the tissue being quite dead. As we have seen, 
the nuclear networks in the mass of endosperm tissue only stain very 
