152 MISSOURI BOTANICAL GARDEN BULLETIN 
Dr. and Mrs. Forrest Shreve, of the Desert Laboratory of 
the Carnegie Institution of Washington, Tucson, Arizona, 
spent a day at the Garden, December 16. At a special semi- 
nar of staff and graduates, Dr. Shreve discussed the work 
on desert vegetation with especial reference to the quantitative 
study of environmental factors. Mrs. Shreve described the 
present status of her work in the measurement of leaf tem- 
peratures, 
The Missouri Botanical Garden Students’ Club, to which 
reference was made in the November Buttertn, held its 
regular semi-monthly meetings in December.’ A paper by 
Mr. G. H. Pring on “The Garden Collection of Orchids” and 
one on “American Cultivation of Orchids” by Mr. N. S. 
Philippi constituted the program of the first meeting. At 
the second meeting Mr. E. J. Palmer, Collector to the Garden 
and the Arnold Arboretum, read a paper on “The Cratae 
Problem.” Other papers of the evening were, “Holi ay 
Plants,” by Mr. Julius Erdman, and “Bulbs and their Cul- 
ture,’ by Mr. Andrew Cella. The club announces the fol- 
lowing rograms for January: January 7, “Twin Falls, 
Towa,” 8. P. Jensen, and “Civic Improvement,” Paul A. 
Kohl; January 21, “Landscape Opportunities in St. Louis,” 
John Noyes, and “Effects Produced by Trees in Landscapes,” 
Clarence Pedlow. The meetings of the club are held regu- 
larly on the first and third Thursdays of each month at 8:15 
o'clock, in the graduate lecture room at Tower Grove and 
Botanical Avenues. All persons interested are cordially in- 
vited to attend the meetings. 
