650 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
Grafting* * * § of the Wild on the Cultivated Carrot.* — M. L. Daniel has 
experimented on the grafting of the wild carrot on a well-established 
and very distinct cultivated variety, and allowing it to produce seed. 
The seedlings from the seeds thus produced manifested a distinct 
approach in characters to those of the host, the phenomena being some- 
what similar to those of hybridisation. 
Exudation of Drops from Leaves.f— Pursuing his researches on this 
subject, Dr. A. Nestler finds, in several genera of Malvaceae, an abundant 
excretion of water, though he was unable to determine whether it was 
effected through trichomes, through the stomates, or through the pecu- 
liarly constructed mucilage-cells. Cut shoots of Tropseolum majus exude 
water in a moist atmosphere not only at the ends of the vascular bundles 
at the margins of the leaves, but also from the stem ; in the latter case 
through the 6tomates. Other examples are afforded by Tradescantia 
viridis, Juncus articulatus, and Dichorisandra discolor . 
(4) Chemical Changes (including Respiration and Fermentation). 
Formation of Albuminoids. :£ — Dr. B. Jacobi gives a resume of the 
results obtained by recent observers on the location and conditions of 
formation of proteids in green plants, which he summarises as follows. 
The synthesis of proteids takes place in the leaves. Under otherwise 
normal conditions of growth, this process may commence in the dark, a 
reaction taking place between the carbohydrates and nitric acid, ammonia, 
and amides. The extent to which this process can proceed in the dark 
depends on the amount of disposable carbohydrates. If these are present 
in large quantities, proteids are formed ; but if the supply is small, the 
process is arrested, in the dark, at the production of amides. Light con- 
tributes indirectly tb the formation of proteids, since it increases the 
supply of carbohydrates. The true source of energy is, therefore, in the 
carbohydrates. 
Action of Diastase on Venom.§ — M. C. Wehrmann confirms La- 
cerda’s observations relative to the digestive power of serpent venom. 
He states that venom does not saccharise starch, nor invert saccharose. 
It does peptonise fibrin. It contains a toxin and a feeble diastase. 
Observations on the action of diastases on venom show that some of 
these bodies possess very active properties, while others are but feebly 
active, and the rest inactive. 
Ptyalin was found to act with remarkable energy on venom, and 
pepsin scarcely at all. Hence, when venom is introduced by the mouth, 
its harmlessness is probably due to the action of the buccal secretion. 
The very active diastases were ptyalin, papain, pancreatin ; the 
feebly active ones, pepsin, rennet, amylase, and the inactive emulsin 
sucraso and oxydase. 
* Comptes Rendus, cxxvii. (1898) pp. 133-5. Cf. this Journal, 1895, p. 72. 
t SB. lc. Akad. Wiss. Wien, cvi. (1897) l te Abtli., pp. 3S7-10G (1 pi.). Cf. this 
Journal, 1897, p. 557. 
X Biol. Centralbl., xviii. (1898) pp. 593-603. 
§ Ann. Inst. Pasteur, xii. (1898) pp. 510-6. 
