5 4 Newcombe. — Cellu lose-E nzymes. 
and Morris 1 , are much more resistant to solution than those 
of the starch-bearing cells. One set of preparations showed, 
in a very strong ferment-solution, these walls completely 
hyaline in twenty-seven hours ; but in most of the solutions 
only after several days. Reinitzer 2 states that the membranes 
of the aleurone-layer of the Barley-endosperm are composed 
mostly of hemicellulose plus a little cellulose, and these walls, 
he says, the Barley-malt-extract will not attack. In this he 
is wrong ; for not only do these walls show by the great 
change in their optical properties that they lose the most 
of their substance, but, after becoming hyaline, they very 
gradually ‘ melt ’ away. I have, with camera-drawings, 
followed very carefully the gradual wasting away of these 
walls for a period of two weeks. By this means I have 
seen exposed walls shorten and shorten and finally disappear. 
There is not the slightest doubt, therefore, that the Barley- 
malt-extract is capable of dissolving wholly the walls of the 
aleurone-layer. 
Brown and Morris 3 have described the solution of the thin 
walls of the endosperm of the Barley as showing the same 
phenomena in normal germination of the grain and in the 
extracted enzyme. They found first a swelling of the 
membranes, then a stratification, then a breaking up into 
spindles which finally disappeared, the middle lamella dis- 
appearing last of all. My own observations confirm these in 
a general way. But I have found that the shredded appear- 
ance of the membrane, which Brown and Morris evidently 
referred to as a spindle-structure, is followed always by the 
appearance of a middle, narrow, bright band which is the 
middle lamella, flanked on each side by a broad, hyaline 
band, and this last bounded against the cell-lumen by a very 
narrow, bright band. In other words, the first part of the 
wall to become hyaline is a strip, on each side, between the 
middle of the wall and the free edge. The resistant band 
1 Jour. Chem. Soc. Lond., 57, p. 497. 
2 Ueber das zellwandlosende Enzym der Gerste : Zeitschr. f. physiol. Chemie, 
xxiii. 190. 3 L. c. 
