408 The Botanical Gazette. [November, 
1. Destructive metabolism in plants results in the decom- 
position of protoplasm, with the production of CO, and H,0. 
The residue may probably be again combined with C, H, and 
O, to rebuild protoplasm. Can this be done in the green 
leaves? Is it accomplished there? For such repair we know 
that carbohydrates disappear, and that such repair is going 
on in allliving parts, whether green or not. _ It is conceded 
that in no part not green could H,CO, be used in this way. 
Presumptively, therefore, it is not so used in these parts. 
2. The amount of H,CO, used by the plant under normal 
illumination is much greater than necessary to repair waste, 
and also much greater than the amount necessary to form t 
starch which appears in the chloroplast. To account for this, 
on the supposition that starch and _ similar cart 
arise in the chlorophyll body by the actual decomposition ' 
protoplasm, it is necessary to suppose that in the gps 
body the protoplasm combines C, H, O, N, and S, at ct 
de novo, to form proteids; or else that the products remaining : 
after the starch is formed from protoplasm are continu : 
rebuilt from the C, H, and O, derived from H,COs- a 
is a much more coniplicated process than polyenee ae : 
formic aldehyde, and it is by so much more impro sien 
Moreover it rests, as I believe, upon insufficient observ 
and faulty deductions from these observations. 
Note the point: That carbohydrates may ar t denied; 
composition of protoplasm is, since it is irrelevant, no ase Ol 
but that the recomposition, the repair, of the are C0,i8 
broken down, is accomplished by the direct use 0! ®' 
highly improbable. ; bs 
% ‘On the view that starch arises only from the eget ‘ 
tion of protoplasm, it is impossible to con ” 
why starch is absent from some spermaphy “+h food in eX : 
fungi in general. They are supplied often wit ‘= abundatt | 
cess; in favorable circumstances the protopiee a the pro 
and active, but however abundant the food or actl = 
toplasm it never decomposes into starch. best with animal a 
We shall harmonize vegetable physiology rocesses: one 
physiology by taking a different view of por pi e, so far as 
which is not opposed by any observation yer al side highly : 
I know, and one which is from the chemic upply of 
probable. no a 
The process in my view is this: Assuming 
ise by the de- 
