TABLE OF CONTENTS 
The origin and development of the galls produced by two cedar 
rust fungi (with one text figure and plates XII-XVII) 
J. L. Weimer 241 
No. 5, May 
The perennial scapose Drabas of North America 
Edwin Blake Payson 253 
The osmotic concentration of the tissue fluids of Jamaican mon- 
tane rain-forest vegetation 
J. Arthur Harris and John V. Lawrence 268 
The viability of radish seeds (Raphanus sativus L.) as affected 
by high temperatures and water content (with one text figure) 
H. G. Waggoner 299 
No. 6, June 
The taxonomy of the Agaricaceae William A. Murrill 315 
Observations on forest tree rusts (with two text figures) 
James R. Weir and Ernest Hubert 327 
Endothia pigments I. (with six text figures) 
LoN A. Hawkins and Neil E. Stevens 336 
Observations on an Achlya lacking sexual reproduction (with 
plate XVHI) Wm. H. Weston 354 
The rusts occurring on the genus Fritillaria (with three text 
figures) • Charles C. Rees 368 
No. 7, July 
Fertility in Cichorium intybus: the sporadic occurrence of self- 
fertile plants among the progeny of self-sterile plants (with 
two text figures) A. B. Stout 375 
Inheritance of endosperm color in maize Orland E. White 396 
The influence of light and chlorophyll formation on the minimum 
toxic concentration of magnesium nitrate for the squash 
(with two text figures).. R. B. Harvey and R. H. True 407 
The use of the vibration galvanometer with a 60-cycle alternating 
current in the measurement of the conductivity of electrolytes 
(with one text figure) Newton B. Green 411 
Immunochemical studies of the plant proteins: proteins of the 
wheat seed and other cereals. Study IX. . R. P. Wodehouse 417 
The toxicity of galactose and mannose for green plants and the 
antagonistic action of other sugars toward these (with four 
text figures) Lewis Knudson 430 
