382 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
that they comprise several distinct substances of characteristic reactions 
and composition. The most noteworthy of these is zein, or maize-fibrin, 
characterized by its high content of carbon, by its resistance to the action 
of dilute alkalies, and by the ease with which it is converted into an 
insoluble modification on being warmed with water or with very weak 
alcohol. Zein is soluble in warm dilute alcohol, insoluble in water. 
Tannins in the Living Cell.* * * § — Herr K. Biittner gives a list of 24 
reagents for the presence of tannins in the living cell, and adds the fol- 
lowing remarks. Substances which give the reactions of tannin are found 
in varying proportions, often considerable, in larger or smaller vacuoles 
in the cell-sap. In such vacuoles no membrane could be detected. The 
chlorophyll-bodies, pyrenoids, nuclei, or nucleoles, never show a tannin- 
reaction in the living cell ; and this reaction is not due to solid bodies 
previously formed in the living cell. Septa sometimes exhibit the re- 
actions of tannin. Some species of Crucifer® examined contained no 
tannin. 
Alkaloids of the Solanaceae.f — Herr W. Schiitte summarizes his 
conclusions thus: — (1) The younger roots of wild belladonna contain 
only liyoscyamine, while the older roots contain atropine as well as 
hyoscyamine, but only in small proportion. (2) The ripe berries of 
Atropa belladonna nigra contain atropine and hyoscyamine ; those of the 
wild plant contain atropine only, and the ripe fruit of A. belladonna 
lutea contains another base perhaps identical with atropamine. (3) The 
leaves of the yellow and black-fruited wild A. belladonna contain 
hyoscyamine and a small quantity of atropine. (4) Fresh and old 
seeds of Datura stramonium contain chiefly hyoscyamine. (5) Solanum 
tuberosum contains, besides betaine, an alkaloid which causes mydriasis. 
(6) The mydriatic alkaloid contained in Lycium barbarum and Solanum 
nigrum exists only in small quantities, and appears to be identical with 
the base contained in S. tuberosum. (7) The leaves of Nicutiana Tabacum 
also contain traces of mydriatic alkaloids. (8) In the seeds, leaves, and 
root of Anisodus l arid us, gathered in autumn, hyoscyamine only has a 
pre-existence. 
Hyoscyamine in the Lettuce.} — Mr. T. S. Dymond describes the 
method by which he obtained a crystalline alkaloid from the lettuce, 
which on examination was found to be hyoscyamine. It is probably to 
this alkaloid that the sedative and anodyne action of the preparations of 
the plant is due ; and it is a fact of special importance, as hitherto no 
alkaloid belonging to the mydriatic group has been found in a plant not 
belonging to the Natural Order Solanace®. 
(3) Structure of Tissues. 
Laticiferous System of Papaveracese.§ — M. J. Leger states that in 
some species of Papaverace® — Eschsclioltzia calif ornica, E. tenuifolia, and 
* ‘ Ueb. Gerbsiiure React, in d. lebenden Pflanzenzelle,’ Erlnngen, 1890, 63 pp. 
See Bot. Ceutialbl., 1891, Beih., p. 513. 
t Arch. Pharm., pp. 492-531. See Journ. Chern. Soc., 1892, Abatr., p. 231. 
j Journ. Chem. Soc., 1892, pp. 90-4. 
§ Bull. Soc. Linn, dc Normandie, v. See Bonnier’s Rev. Gen. de Bot. iv. (1892) 
p. 139, 
