378 EIBLIOGEAPHY.
gigkeit der Keimung von der Temperatur. Pringsheim's Jalir- biicher fur Wiss. Botanik. Bd. ii. pp. 338-377.
The author's inquiries, conducted chiefly in the winters 1857-8 and 1858-9, were instituted with a view to determine the extremes of temperature at which the seeds of various species would germi- nate, the rate of development of the organs as affected by diverse or constant temperatures, and the effect of a fixed temperature on the different stages of development of germinating plants. The results of experiments (upon Maize, Barley, Wheat, Phaseolus multiflorus, Pea, Bean, Gucurbita JPepo and other species) are detailed — (1) on the change in the rate of extension of germi- nating rootlets and ascending organs under like temperatures : (2) the temperature most favourable to rapid development of the germ: (3) the minima and maxima at which germination takes place : and (4) the dependence of ulterior development on temperature.
A criticism upon A. DeCandolle's theory of the relation of vegetation to temperature, (Bibl. Geneve, Mars, 1860, and ' Geog. Bot.' i. 51), and a proposed formula for the expression of the empirical relation of temperature to vegetation, are added to the above details.
Savi, Pieteo. — Nota sulla morfologia e micrografia degli organi delle Cicadacee. II Nuovo Cemento, xii. 1860. Ext. pp. 8.
Schacht, H. — Der Baum. Studien iiber Bau und Leben der hoheren Gewachse. 2nd edition, 4 plates and 227 wood engravings. 8vo. Berlin, 1860.
De Maculis in plantarum vasis cellulisque lignosis obviis. An.
Sc. Nat. Bot. xiii. pp. 218-235.
Sciiafenee, Dr. — Zur Entwicklungsgeschichte des Embryos und Samens von Leucojum vernum. Flora, 1860, 577-582. With 1 plate.
Appendages of delicate membranous texture are described, developed from the germinal vesicle and projecting beyond the apex of the embryo sac. They are lost when the embryo is matured.
Schenk, Peoe. — Ueber Parthenogenesis im Pflanzenreiche. Wiirz. Nat. Z. Bd. i. pp. 85-9.
The result of experiments, chiefly upon Cannabis saliva and Mercurialis annua. No female flower, which had been cut oft' from the access of pollen, perfected fruit.
Sciilechtendal, D. F. L. v. — Nachtrag zur Geschichte der Sonnen- blume {Heliantlius annuus, L.) Bot. Z. 1860, pp. 349-350.
Abnorme Weizenahren, Bot. Z. 1860, 381-3. _
Sciilotthauber, Dr. — Zunahme der Temperatur in der unteren Region der Atmosphare, sowie Erklarung und Einfluss dieser Erscheinung auf die Vegetation. Bonplandia, 1860, pp. 371-3.
ScnoENEEELo, W. — Sur le mode de Vegetation de Y Aldrovanda vesi-
