72 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
u or a reducing sugar. No bacteria could be detected in it. Under 
ordinary circumstances the sessile glands do not secrete any digesting 
fluid. Tlie secretion attracts great quantities of insects, the bodies of 
which are digested and absorbed ; and the same is the case with flesh and 
fibrin, and especially with boiled white of egg. Although the sessile 
glands do not themselves secrete a digesting fluid, they assist this process 
in the stalked glands by carrying off the products of digestion. No 
diastatic ferment is present in the secretion. 
Symbiosis as the result of Grafting.* * * § — Prof. H. Vochting has suc- 
ceded in obtaining a number of successful plants, resulting from the 
grafting of Heliantiius tuberosus on E. annuus. In opposition to the 
statement of previous observers, he found no “ graft-hybridization ” to 
take place ; each species preserved fully its own characters. There was 
no tendency to the formation of tubers by E. annuus, nor did this species 
produce inulin. Corresponding results were obtained by grafting E. 
annuus on H. tuberosus. Each species ful fils its part in the life of the sym- 
biont, but no transference of properties takes place from one to the other. 
Grafting of Herbaceous Plants.f — As the result of a number of 
experiments, chiefly on Cruciferse and Leguminosae, M. L. Daniel states 
that graft-hybrids may be produced in herbaceous plants, and that these 
can be endowed with new alimentary powers by grafting them on plants 
which excel them in this respect, and sowing the seeds produced on the 
graft. Plants differ greatly in their power of acquiring new characters. 
It appears to be especially strongly marked in the Cruciferae. With 
etiolated herbaceous plants all attempts at grafting were unsuccessful. 
Vitality and Germination of Seeds.J — From experiments made on 
the germination of a number of seeds, Mr. A. J. Ewart concludes that 
the power possessed by certain seeds of resistiug the action of absolute 
alcohol is due to the relative impermeability of the seed-coat, and to the 
inherent vitality of the protoplasm of the seed, and more especially of 
the embryo. The protoplasm of seeds presents a marked difference from 
that of ordinary protoplasm. It is more stable, of a less complex nature, 
and contains a smaller proportion of water. The latent period of germi - 
nation of seeds, i. e. the period before the evolution of carbon dioxide 
commences, varies with the species. The radicle exhibits a distinct 
oxy tropic irritability. 
Influence of the different Rays of Light on Assimilation and 
Transpiration. § — From a series of experiments carried on on a variety 
of different plants, Herr E. Wollny finds that yellow light has the 
greatest power of producing organic substances ; next the red ; while 
blue light has a remarkably prejudicial effect on the development of the 
reproductive organs. It is, therefore, the most refrangible (chemical) 
rays which take the least part in metabolism, the assimilation of carbon 
being carried on mainly by the less refrangible (illuminating) rays. The 
* SB. K. Preuss. Akad. Wiss. Berlin, 1894, pp. 705-21 (1 pi.). 
t Comptes Rendus, cxviii. (1894) pp. 992-5; Rev. Gen. de Bot. (Bonnier) vi. 
<1894) pp. 356-69 (2 pis.). Of. this Journal, 1894, p. 476. 
t Trans. Liverpool Biol. Soc., viii. (1894) pp. 207-47. 
§ "VVollny’s Forsch. a. d. Geb. d. Agriculturphysik, xvii. (1894) pp. 317-32. See 
Bot. Centralbl., lx. (1894) p. 216. 
