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SUMMARY OF CURRENT RESEARCHES RELATING TO 
Development of the Buds in the Potato.* * * § — Tt has long been ob- 
served that the buds in the anterior or upper half of a potato develope 
earlier and more rapidly than those in the posterior or lower half. 
M. A. Prunet states that in young potatoes the nutritive substances are 
distributed uniformly through the tuber ; but that at a later period a 
flow of these substances takes place from the lower towards the upper 
part ; so that the buds in this portion have a larger supply of food- 
material when they begin to germinate than have those in the lower part. 
Grafting of Cruciferse.j — M. L. Daniel finds it possible to graft 
successively different species of Cruciferae upon one another, even when 
they belong to different genera, in a great variety of ways, viz. : — peren- 
nial or biennial on annual species, and vice versa , or an aerial stem on an 
aerial stem, or an underground on an underground stem, and even an 
aerial on an underground stem. In many cases it was found that the 
graft influences the host-plant by imparting to it in some degree its 
character as to durability, i. e. whether annual, biennial, or perennial. 
The grafting of a portion of the descending on a portion of the ascend- 
ing axis does not appear to have been accomplished before. 
Regeneration of Split Roots4 — Prom observations made by Herr 
G. Lopriore on a large number of plants, he concludes that under 
favourable conditions the regeneration of split roots is possible iu all 
plants, whether herbaceous or woody. In this renewal all the tissues 
partake, cortex, epiderm, and vascular system. In the region which 
borders the incision a healing tissue is first formed, and soon afterwards 
in it a meristem composed of cells arranged parallel to the surface of 
the wound appears. From this the new tissues are again formed. The 
process varies in Monocotyledons and Dicotyledons, and several different 
types are described. 
Revivification of Desiccated Plants.§ — Prof. G. Bonnier concludes, 
from a series of experiments, that many cultivated plants may be dried 
up after a shorter or longer period of germination, that they may be 
preserved in this condition, and may again pass into a state of active 
development, if replaced in favourable conditions. It is the water 
above all, which, abandoning or combining with the protoplasm, plays 
the principal part in the alternations of diminished or increased vitality. 
The water of the membranes of grains of starch, &c., appears to play 
only a secondary part. In the species studied, the wheat, the pea, and 
the bean are those which present the phenomenon of revivification in a 
most advanced stage of development. When the roots or the apex of 
the stem do not themselves resume the state of active vitality after 
desiccation, the plant developes by means of new roots or by adventitious 
buds. Finally, if we study these plants in the course of revivification, 
from the point of view of the gaseous exchanges and of the disengaged 
heat, we find phenomena analogous to those of the germination of seeds, 
except that the first period (during which the relation of the exchanged 
gases borders on unity and in which the disengaged heat is less than 
* Comptes Rendus, cxiv. (1892) pp. 1079-81. 
f Tom. cit., pp. 1294-6. Cf. this Journal, ante , p. 67. 
X Ber. Deutsch. Bot. Gesell , x. (1892) pp. 76-83. 
§ Rev. Gen. de Bot. (Bonnier), iv. (1892) pp. 193-201. 
