74 
gators on the relation of manganese to agriculture, 
the author presented results obtained by growing 
wheat in manganese-free sand and in cultural so- 
lutions, with and without the addition of manga- 
nese. Z 
Wheat plants grown to within a few weeks of 
maturity in cultural solutions containing manga- 
nese and others of the same age in which the man- 
ganese had been omitted, were on exhibition. 
Where manganese had been added to the cultural 
solutions the plants were apparently normal in 
every respect, whereas the plants grown in solu- 
tions containing no manganese showed a retarded 
growth in the blades, stalks and roots, as com- 
pared with the plants of the same age receiving 
manganese. There was evidence of lack of the 
proper development of chlorophyl in the plants re- 
ceiving no manganese and the blades of these 
plants exhibited a drooping appearance in that 
they were not able to hold themselves erect, which 
was quite characteristic and not to be observed 
in any of the plants receiving manganese. ~ 
The author concludes from his experiments that 
manganese plays a more important role in the 
growth of wheat than has hitherto been suspected. 
Formation of petroleum: C. J. Norwoop. (By 
title.) 
Cryoscopic work with an ordinary thermometer: 
C. C. Kipuineer. It has been found possible to 
read small temperature intervals on a common 
thermometer, within an accuracy of 1/100 degree, 
by measurements of the parallax on an auxiliary 
scale equipped with a sliding peep-sight. 
Several heretofore troublesome sources of error 
in the boiling point method of determining molec- 
ular weights have been eliminated by using but 
one point as reference on a thermometer scale, 
having established this point by the use of a 
known substance with a high degree of purity. 
This procedure eliminates the need of a calibrated 
thermometer. 
The use of the parallax method is suggested in 
the estimation of fractional parts of a scale di- 
vision on other instruments than the thermometer. 
Generalization on the mean-value theorem: H. 
H. Downine. 
Magnolia fraseri: does it occur in Kentucky? 
FRANK T. McFARLAND. 
List of fungi from Kentucky: FRanK T. Mc- 
FARLAND. 
An equation balance: E. Li. REES. 
A method of constructing the graph of an equa- 
tion in which the variables may be separated: E. 
L. REEs. 
SCIENCE 
[N. 8. Vou. XLVIII. No. 1229 
Protein metabolism in the growing chick: G. D. 
BucKNER and others. (By title.) 
Review and observations on the mosaic disease 
of tobacco: G. C. Rourt. The author reviews the 
work of other investigators and reports observa- 
tions of his own upon the disease in experimental 
plots of different varieties of tobacco. He favors 
the view that the best way to combat the disease 
will be to develop a resistant strain of tobacco. 
Dr. J. A. Detlefsen, of the department of genet- 
ies of the University of Illinois, addressed the 
academy on ‘‘Laws governing the transmission of 
characters from parent to offspring.’’ 
The speaker gave a brief review of the search 
by investigators for the cause or causes of eyolu- 
tion. He then explained the law for the trans- 
mission of mono-hybrids, di-hybrids and tri-hy- 
brids. He presented these laws and illustrated 
them so well that there was left no doubt in the 
minds of workers in other fields that great progress 
has been made in genetics in recent years. 
He threw upon the screen the tables giving the 
result of his own breeding experiments to show 
how nearly actual counts agree with the mathemat- 
ical expectation, in the laws of transmission. It is 
remarkable how nearly actual counts of animals 
bred agree with the expectation of what, by Men- 
del’s law, they should be. 
Among other items of business, a resolution was 
passed offering the services of the academy to the 
U. S. government for any war work in which this 
organization might be of assistance. 
Officers were elected as follows: 
J. E. Barton, Frankfort, President; P. P. Boyd, 
Lexington, Vice-president; A. M. Peter, Lexing- 
ton, Secretary; J. S. McHargue, Lexington, Treas- 
urer. 
ALFRED M. PETER, 
Secretary 
SCIENCE 
A Weekly Journal devoted to the Advancement of 
Science, publishing the official notices and pro- 
ceedings of the American Association for 
the Advancement of Science 
Published every Friday by 
THE SCIENCE PRESS 
LANCASTER, PA. GARRISON, N. Y. 
NEW YORK, N. Y. 
Entered in the post-office at Lancaster, Pa., as second class matter 
