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Al the meeting of the Section, April 18th, 1859, Mr. H. A. 
Horst read a Paper on the “ Structure of 
Starch Granules.” 
——. 
Mr. Horst gives a long series of quotations from the 
works of the most celebrated writers on this subject, illus- 
trative of the various opinions entertained by high au- 
thorities on the Structure of these Granules, showing the 
prominent opinion on the subject to be, that they owe the 
peculiar striated appearance of their surfaces to their being 
formed of a number of concentric layers converging to a 
nucleus. This theory, however, Mr. Hurst disputes ; and 
after giving a detailed account of the manner in which the 
granules behave under the influence of various chemical 
reagents, proceeds to support a theory of his own on the 
subject as follows : 
“ Payen, in his Mémoires sur le développement des Végé- 
taux, in 1842, gives plates of the appearances of Starch 
Granules, which on first inspection appear to prove satis- 
factorily the concentric layer theory; but on further ex- 
amination it will be found that they require to be roasted, 
iodized, acidulated, and otherwise acted on by chemical 
agency to such an extent that the results cannot be ac- 
cepted as evidence of structure existing before all these 
influences were brought to bear upon them; and in con- 
nection with this I would remark that immersing an object 
for three weeks in iodine, as done by Dr. Allman, is hardly 
a fair test, and may very possibly cause the concentric 
layers, to prove the existence of which it is used. Mr. 
Tuffen West remarks, and I consider very justly, that 
