558 8UMMARY OF CURRENT RESEARCHES RELATING TO 
of the cell. Sexual reproduction is regarded by the author as a con- 
sumption by the organism of its own substance (autophagy). 
Function of Calcium Salts.* — Herr O. Loew lays stress on the fact 
that, although the presence of some salt of calcium appears to be essential 
to the growth of most plants, this is not the case with the lower Fungi 
or with one lowly organised Alga ( Palmella ). He holds that the nucleus 
at a certain period of development, and the chlorophyll-bodies except at 
their very earliest stage, require calcium, and make use of its protein- 
compounds. Salts of strontium produce no injurious effect so long as 
the plant is supplied with sufficient salts of calcium. Different fungi 
exhibit different results as to the possibility of substituting rubidium for 
calcium. 
Power of Isolated Chlorophyll-Grains to give out Oxygen.f— 
Dr. L. Kny replies to the strictures of Ewart if on his previous paper, 
and maintains the correctness of his former conclusions. In the same 
examples as those employed by Ewart — Vallisneria spiralis , Selaginella 
helvetica , Catliarinea undulata, Funaria liygromeirica — he was never able 
to detect any evolution of oxygen from the chlorophyll-grains when 
completely separated from the surrounding cytoplasm. 
In reply Dr. A. J. Ewart § claims that Kny’s results practically 
coincide with his own. 
Growth of Lilium Martagon.||— Herr A. Rimpach has studied the 
growth of Lilium Martagon from the seed. The first foliage-leaf appears 
in the second spring; its basal portion swells, and becomes filled with 
starch ; for several successive years only one fresh foliage-leaf is pro- 
duced annually by the small bulb, which is gradually dragged downwards 
by the contractile roots, always in an erect position. After the ascending 
stem has begun to develop, no fresh root-leaves are produced. The 
ordinary mode of reproduction of the plant is by seed. In the con- 
tractile roots the contractile tissue is the whole of the inner cortex ; the 
outer cortex, the central vascular cylinder, and the endoderm taking no 
part in the contraction. The mature plant produces also a rosette of 
small roots which extend horizontally, and are densely covered with 
root-hairs. They serve to sustain the stem in an erect position, as well 
as performing a nutritive function. 
Growth of Root-hairs and Rhizoids.1T — Herr C. Sokolowa has studied 
the phenomena connected with the growth of the root-hairs in seedlings 
of flowering plants — Sinapis alba, Brassica Napus , Cucumis sativus, — and 
the rliizoids of cryptogams — Marchantia polymorpha, Lunularia vulgaris. 
In all these cases not only is the growth limited to a special region, the 
apical cap, but in this region only a particular spot is in active growth 
at any one moment, the whole cap bending towards the side on which 
this spot is located. 
With regard to the physiology of growth, the author holds — as the 
* Eot. Centralb]., lxxiv. (1898) pp. 202-5, 257-65. 
t Op. cit., lxxiii. (1898) pp. 426-39. Cf. this Journal, ante , p. 101. 
J Cf. this Journal, ante , p. 206. § Op. cit., lxxv. (1898) p. 33. 
1| Ber. Deutsch. Bot. Geselh, xvi. (1888) pp. 104-10 (1 ph). 
IT Bull. Soc. Imp. Nat. Moscou, 1897, pp. 167-277 (3 pis. and 22 figs.) (German). 
