MISSOURI BOTANICAL GARDEN BULLETIN 7 
Scientific and Extension Lectwres:—The following are the 
more important given by members of the scientific and Gar- 
den staffs during 1918: 
B. M. Duggar, January 1, before the Brooklyn Institute 
of Arts and Sciences, “The Significance of Plant Diseases 
and the General Problems of Parasitism.” 
B. M. Duggar, February 4, before the St. Louis section of 
the American Chemical Society, “Some Refinements in the 
Indicator Method of Hydrogen-Ion Determinations.” 
G. H. Pring, February 20, before the St. Louis Natural. 
History Museum Association, “Insect Pollination in 
Flowers.” 
George T. Moore, March 4, at Graham Memorial Chapel, 
Washington University, ‘Vegetable Gardens: Their Use and 
Misuse.’ 
Alexander Lurie, March 6, before the St. Louis Gardeners’ 
Club, “Tree Surgery.” 
Alexander Lurie, March 8, before the Wellston High 
School, ‘Thrift Gardens.” 
B. M. Duggar, March 11, at Graham Memorial Chapel, 
Washington University, “Production and Food Values.” 
George T. Moore, March 12, before the St. Louis Garden 
Club, “Lawns.” 
Alexander Lurie, March 18, at Graham Memorial Chapel, 
Washington University, “How to Plant.” 
W. S. Wells, March 18, at the Carnegie Library, Belle- 
ville, “Thrift Gardens.” 
Alexander Lurie, March 25, at Graham Memorial Chapel, 
Washington University, “How to Plant.” 
Alexander Lurie, April 3, before the St. Louis Association 
. Gardeners, “Diseases and Insects Injurious to Thrift Gar- 
ens.” 
G. H. Pring, April 3, before the St. Louis Association of 
Gardeners, ‘‘Vegetable Planting.” 
Alexander Lurie, April 4, before the East St. Louis Civic 
Association, “Trees.” 
W.S. Wells, April 9, before the Bryan-Mullanphy Parent- 
Teachers’ Association, “Thrift Gardens.” 
George T. Moore, April 13, before the Town Club, “Gar- 
dening.” 
B. M. Duggar, December 10, before the St. Louis Garden 
riba RA Constituents from the Soil and Their Use in 
the Plant.’ 
Graduates, Fellows, and Investigators —The number of 
duate students qualifying for work and accepted during 
917-18 was limited by war conditions, and it represents the 
