CONTENTS 
Britton, NATHANIEL Lorp. Studies of West Indian Plants— 
Griccs, Ropert F. Observations on the behavior of some species at thie 
edges of their ranges - - 
RoBInson, WINIFRED J. A taxonomic sede of this Preridophyta of thie 
Hawaiian Islands—IV (plates 1, 2) - 51 
BICKNELL, EUGENE P. The ferns and flowering es of Nantncket ot I 7 
RYDBERG, P. A. Ae ered notes on the Rocky Mountain region 
it Origin of the alpine flor: - 89 
MILLER, FRED A. The eaten, of sascil baal ainiis - - 105 
FIsHER, G. CLypE. Seed achat tsa in the genus Suze (nates 3-6) 
[To be concluded.] - 137 
DopcE, B. O. The morphological relationships of he Fl tides sa the 
Ascomycetes - 157 
HARPER, ROLAND M. The “Pocosin’ ' of Pike County, eae ba and its 
bearing on certain problems of succession - 2 
FIsHER, G. CLYDE. Seed ape ee in the genus Peperomia (rates 8) 
2 
[Concluded.] - I 
Harris, J. ARTHUR. ee the diana bieatea ‘he sities of oe: 
formed and the number of seeds developing in Cercis- - - 243 
KuNKEL, Louis Otro. Physical and chemical factors infuencing the 
toxicity of inorganic salts to Monilia apphegts {(Mont.) S. “ - 265 
Berry, Epwarp WILBER. Contributions to the Mesozoic ess of the 
Atlantic coastal plain, X.—Maryland- - 295 
BAILEY, Ober: on. The wild cotton pent (Thurber thespesioides) in 
Ariz - - 301 
SLOSSON, Gee Notes on two .N oon Annecivas fers (plat 7 - + 307 
RypBeErG, P. A. Notes on Rosaceae—VII - 319 
ATWELL, Rut S. The appearance of polar adic j in he selmi A ; 
tissue of Ricciocarpus natans (L.) Corda. (plate 8) - 333 
Turesson, GOTE. Slope exposure as a factor in the SaiGhation of Poe: 
dotsuga taxifolia in arid parts of Washington - - 337 
Vesta, ArtHUR G. A black-soil prairie station in en ieaticn Illinois - 351 
Bowman, Howarp H. M. Mechanical tissue development in certain North 
American vines - - - . - - - - - - - 3 
Howe, R. HEBER, JR. The nomenclature of the genus Usnea (plates 9-14) 373 
Griccs, Ropert F. Observations on the Saat of the forest in the Kodiak 
region of Alaska- - 
Benepict, Ratpu C. A revision of the genus Vite: if E. Seah, 
pecies of the subgenus Radiovittaria (plates 15-20) ~ 391: 
BICKNELL, EUGENE P._ The fernsand flowering plants of N antackes Dill 4II 
ALLARD, H. A. A review of investigations of the mosaic disease of tobacco, 
together with a bibliography of - more important contributions - 435 
