92 MISSOURI BOTANICAL GARDEN BULLETIN 
leaves form and attain nearly or quite their full size at a 
season when there is insufficient warmth for the formation 
of chromatophores and chlorophyll pigment, though enough 
for growth.’’ While this may possibly be the cause in the 
natural habitat, it cannot be entirely so in the present case, 
for the burl was kept at room temperature (70°F.) from the 
start. It seems therefore probable that other factors are in- 
volved. It is of interest to note that Peirce transplanted one 
of his shoots to Palo Alto, of which he says: ‘‘at least one 
leaf became pale green over half its surface on either side 
of the midrib.’? Whether the conditions under which our 
specimen grew, which caused it to turn green throughout, 
were sufficiently different to show this variance with Peirce’s 
specimen, further experimental work will have to determine. 
NOTES 
Mr. L. P. Jensen, Arboriculturist to the Garden, gave an 
illustrated lecture on ‘‘ Wild Flowers’’ before the Chautauqua 
Association, Piasa, Ill., August 2. 
Mr. G. H. Pring, Horticulturist to the Garden, spoke before 
the Maryland Terrace Association, September 24, on ‘‘The 
Care of Lawns and Shrubbery.’’ 
Mr. Pring’s lecture, ‘‘Collecting Orchids in Colombia,’’ was 
broadeasted from the Grand Leader Radio Station, August 
20, and from the Post-Dispatch Station, September 11. 
Recent visitors to the Garden include Professor John T. 
Buchholz, professor of botany, University of Arizona, Profes- 
sor John H. Schaffner, professor of botany, Ohio State Uni- 
versity, and Mr. Fuyuwo Kagawa, government research 
scholar of Japan. 
Mr. L. P. Jensen, Arboriculturist to the Garden, attended 
the convention of the American Institute of Park Executives 
held in Kansas City, September 10-16, and on September 11 
presented a paper before the convention on ‘‘Arboretums in 
Connection with the Park System.’’ 
The Dahlia Show, which will be the first of its kind in St. 
Louis, will be held under the auspices of the Garden in the 
floral display house, October 10 and 11. The premium lists 
which include both amateur and commercial entries will be 
mailed upon application to the Director. 
