400 SUMMARY OF CURRENT RESEARCHES RELATING TO 
of tlie phenomena connected with their swelling. He regards as unne- 
cessary the use of the terms a-amylose and /3-amylose, as proposed by 
Meyer, the former being practically identical with the farinose, the 
latter with the granulose of earlier writers. The term amylose might 
then be retained for the substance resulting from the conversion of 
granulose into paste. He dissents further from Meyer’s theory as to 
the mode in which water penetrates into the substance of the starch- 
grain. The author does not agree with Meyer as to the difference 
between ordinary swelling and conversion into paste ; both consist in 
an absorption of water into the substance of the starch ; but while, when 
starch dissolves in cold water, the unchanged granulose absorbs but little 
water, and preserves its solid consistence and its crystalline structure ; 
when converted into paste it passes over into a different substance which 
absorbs much more water, and forms, in the swollen condition, dimorphic 
mucilaginous drops. Swelling is simply a special case of solution, in 
which a fluid substance is dissolved in a solid substance. Bodies capable 
of swelling are those which are able to dissolve certain fluids. The 
author does not consider that Meyer brings forward satisfactory evidence 
of his statements that every starch-grain is completely and constantly 
surrounded by the substance of its chromatophore, and that the cliroma- 
tophore-envelope is also the sole seat of the formation of diastase. In 
all probability it is formed in the cytoplasm. 
Soluble Starch.* — M. P. Guerin finds a substance possessed of the 
chemical properties of starch dissolved in the cell-sap in Cola acuminata 
and C. Ballayi, belonging to the Sterculiacese. The cells in which this 
substance occurs are almost exclusively epidermal; but it has been 
found also in the mucilage canals. In the lower epiderm of the 
leaves, starch-grains of the ordinary kind are present in the same 
cells as the soluble starch. 
Aromatic Principles in Leaves.f — M. G. Jacquemin finds that with 
plants which bear fragrant or sapid fruits — as the apple, pear, raspberry 
— if the leaves are placed in a saccharine fluid with Saccharomyces or 
some other enzyme, the fluid will acquire the flavour and odour of the 
fruit, and the alcohol obtained by distillation from this liquid will possess 
the corresponding bouquet. 
Active Principles of the Aroidese.J — Mdlle. J. Chauliaguet and 
MM. A. Hebert and F. Heim have investigated the nature of the poison- 
ous principles in several species of Aroidese, chiefly Arum maculatum, 
A. italicum, and Arisarum vulgar e. They find the constant presence of 
a glucosidc, with the characters of a saponin, in the underground organs 
and the leaves. The alkaloid was extracted, and was found to correspond 
in all its properties with the conicin of the hemlock, though somewhat 
less active. A similar volatile alkaloid exists in the tubercles of Cala- 
dium bulbosum and Amorjdiophallus Bivieri. The author was unable to 
confirm the occurrence of hydrocyanic acid, affirmed by previous writers. 
Latex and its Function. § — From the fact that some of the chief 
constituents of latex are starch, proteids, and sugar, and that the pro- 
* Bull. Soc. Bot. France, xliv. (1897) pp. 91-5. 
t Comptes Rendus, cxxv. (1897) pp. 114-6. j Op. cit., cxxiv. pp. 1368-70. 
§ Ann. of Bot., xi. (1897) pp. 334-9. 
