1910] CURRENT LITERATURE 73 
Interaction between scion and stock.—MEveER and ScHmipt" have produced 
a voluminous article on the interchange of substances and mutual influence between 
stock and scion in a heteroplastic graft. The introduction and review of litera- 
ture occupy 48 pages, and 33 pages are given to the statement of results and the 
summary. One is compelled to think that the article could have been advantage- 
ously condensed to half the space. The authors mention that interchange of 
carbohydrates was already fully worked out, while the previous work on move- 
ment of aplastic and other substances is very unsatisfactory. They direct their 
attention to the movement, formation, and storage of alkaloids, using Nicotiana 
Tabacum as scion on N. affinis and Solanum tuberosum as stocks, and Datura 
Stramonium as scion on Solanum Lycopersicum and S. tuberosum. ey 
that alkaloids can pass from scion to stock; but the movement is very slow, and 
apparently takes place through the parenchyma and not through the sieve tubes. 
ith N. Tabacum, normally rich in nicotin, as scion, and N. affinis, normally 
poor in nicotin, as stock, the latter comes to contain many times its normal amount 
of nicotin, and even ten times as'much as the scion; while the scion becomes 
relatively poor in it. With S. tuberosum as stock for N. Tabacum, the periderm 
cells of the former become the main storage tissue for the nicotin. It is most 
abundant in the tissue of the stock just below the graft, and decreases in amount 
as the cells are more distant; while in the tuber none at all or only traces appear.— 
WILLIAM CROCKER. 
Living cells and extreme temperatures. —GEORGEVITCH,*? in investigating 
candicans. They were kept at 40° C., and —5°C., killed and fixed at the same 
temperature, and the effect of these seteate noted. Ata temperature of + 40° C., 
the cytoplasm coagulates and forms small clumps of dark-staining material. At 
low temperatures the cytoplasm becomes vacuolate, and the coordination in the 
action of the spindle fibers is broken up, which results in the distribution of 
chromosomes between the poles. The activity of the kinoplasm is decreased 
by low temperature and increased by high temperature. There result larger 
spindles with stronger fibers, more rapid transport of chromosomes, and shortened 
duration of nuclear division. Thereby cell wall formation is inhibited and binu- 
cleate cells are of frequent occurrence. The chromosomes often form chains, 
due to the irregular transport toward the poles. In cold preparations the nucleus 
often takes on an amoeboid form, also in the warm, but not to such an extent. 
In general it can be said that high temperatures favor development of chromatic 
MEvER, ARTHUR, and ScumiptT, Ernst, Ueber die gegenseitige Beeinflussung 
der Sy avasies heteroplastischer Transplantationen mit besonderer Beriicksichtigung 
der shone: der Alkaloide durch die Pfropfstellen. Flora 100:317-396. figs. 3. 
IQIo 
12 GEORGEVITCH, PETER, Ueber den Einfluss von extremen Temperaturen auf 
die Zellen der Wurzelspitze von Galtonia candicans. Beih. Bot. Centralbl. 25 :127-135- 
Igto. 7 
