1894. | NEW YORK ACADEMY OF SCIENCES. 159 
to find variations in both sexes, as the establishment of a well- 
marked breed of sheep was known to have originated in but a 
single individual. Intercrossing is unquestionably swamping 
in its effects, but natural, as well as artificial selection, could 
overcome its results. Physiogenesis would in the end be often 
iujurious, since in another generation other combinations of 
colors, etc., might be more valuable for protection. 
The action of environment is only valuable as the shock or jar 
which produces variation in an already predisposed organism 
Tooth enamel could hardly be regarded as sufficiently plastic to 
be mechanically modified at certain points to meet necessary 
wear; if slightly plastic the case is one, not of mechanical 
origin, but of organic growth. 
In the absence of Prof. J. A. Allen, his paper on the ‘ Direct 
Action of Physical Conditions as a Factor in Evolution” was 
submitted by the Secretary. 
After a brief note by Prof. Cope the meeting adjourned. 
BASHFORD DEAN, 
Recording Secretary of Biological Section. 
J. F. KEmMpP, 
Recording Secretary. 
March 12th, 1894. 
The regular meeting took the form of a reception and exhibi- 
tion of apparatus, etc., to illustrate the recent progress of 
science. The following departments were represented and were 
under the charge of the chairmen whose names appear opposite: 
Anatomy, Prof. Huntington. 
Mineralogy, Prof. Moses, Mr. Kunz. 
Astronomy, Prof. Rees. 
Paleontology, Dr. J. L. Wortman. 
Botany, Judge Addison Brown. 
Photography, Mr. Van Brunt. 
Chemistry, Prof. Chandler. 
Physics, Prof. Hallock. 
