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December 18. ‘* Heredity and the Origin of Species,” by 
Dr. D. T. MacDougal, before the Barnard Botanical Club, 
at Columbia University. 
The meetings of the Torrey Botanical Club are held in the 
Laboratories eight times during the collegiate year. 
In addition, a number of conferences have been held for 
the advanced pupils of the public schools, and guides have 
been furnished for parties which have been brought to the 
Garden by teachers for the inspection of the collections. 
Material for nature study has also been furnished to a num- 
ber of schools on request. 
The botanical conventions, held bi-weekly in the library, 
continue to be a source of great profit to the entire staff and 
to the botanists of neighboring institutions who attend them. 
These meetings afford an opportunity of presenting the results 
of investigations at an early moment and also give opportunity 
for discussion by specialists in every branch of the subject. 
The following principal subjects have been presented dur- 
ing the year: 
January 18. ‘‘ Hybrids of the Evening-primroses,” by Dr. 
D. T. MacDougal. 
February 8. ‘Tertiary Plants from Maryland,” by Dr. 
Arthur Hollick. 
March 22. ‘* What Constitutes a Leaf in a Fern,” by Pro- 
fessor L. M. Underwood. 
Aprilig. ‘The Behavior of the Pollen-tube in Hous- 
tonia coerulea,” by Mr. C. A. Mathews. 
May 3. ‘*Exploration in the Delta of the Rio Colorado 
and Adjacent Deserts,” by Dr. D. T. MacDougal. 
October 18. <‘‘ Observations on the Physiology of Sto- 
mata,” by Professor F. E. Lloyd. 
November 1. ‘Results of Recent Studies in Evolution,” 
by Dr. D. T. MacDougal. 
November 22. ‘* Ascidia in Fraxznus,” by Dr. G. H. 
Shull. 
December 6. ‘Influence of Radioactive Substances upon 
Plants,” by Dr. C. S. Gager. 
