179 
91. HumMBoLpT, ALEXANDER VON. 
Ideen su elmer ras siognonitk der Gewdachse. 1806. 
First edition. 
92. INGEN-Housz, JOHN. 
Experiments upon vegetables, discovering their great power of 
purifying the common air in the sun-shine, and of injuring it in 
the shade and at night. London, 1779. 
First edition. 
Ingen-Housz acknowledges his indebtedness to Priestley as the 
source of his inspiration. His conclusions were “the result of 
above 500 experiments” (page xiii). He demonstrated that 
green plants take in carbon dioxide and give off oxygen, but only 
in daylight. 
“One leaf of a vine, shut up in an ounce phial, full of air fouled 
by breathing so that a candle would not burn in it, restored this 
air to the goodness of common air in the space of an hour and a 
half. But plants enjoy this privilege only in the day-time, and 
when they grow in unshaded places’ (page 39). 
CCheNosv4l, 9798 100 Os.) 
jan 
93. MENDEL, GREGOR. 
Versuche iiber Pflanzen-Hybriden (in Naturforschender Verein. 
3runn, (Austria). Verhandlungen. Vol. 4, 1866.) 
The famous description of his experiments on peas, made by 
Mendel in the monastery garden at Briinn, was the foundation 
of the scientific study of heredity. 
On page 21 there is an error of fact, since the first hybrid (F,) 
generation of pea seeds (from a cross between “ 
smooth ” and 
“wrinkled ” seed parents) are describec 
as “smooth or wrinkled.” 
Probably this error is due to careless preparation of MS. or care- 
less proof-reading. 
— 
94. Mout, Huco von. 
Vermischte Schriften botanischen Inhalts. 1845. 
A collection of the earlier works of the most important of the 
founders of plant cytology. von Mohl first used the term proto- 
plasm (1846) in its modern sense, to describe the living substance 
of plants and animals. 
