CONTENTS 
RITTON, NATHANIEL Lorp. Studies of West Indian plants—IV I 
Livincston, BurTON E., and EstaBrook, ARTHUR H. Observations on 
the degree of stomatal movement in certain plants - r§ 
Maxon, Witt1am R. Notes on the North American species of Phanero- 
phlebia_ - 23 
Dorsey, M. J. Variation in the Ae structures of Vitis (plates oF ee | 
DAcHNoWSKI, ALFRED. The relation of Ohio bog ih Sa to the chem- 
ical nature of peat soils = - 53 
SEAVER, FrED J. Studies in seein fungi The viability of the 
spores of Pyronema (plate 4) - 3 
BICKNELL, EuGENE P. The ferns and fiowerlie sis of anaa ie 69 
BRAINERD, Ezra. Violet acai between species of the mews group 
(plates 5-7) 85 
RYDBERG, PER AXEL. Studies on de Rocky's Mountain fora—XXVI - 99 
Fromme, Frep D. Sexual fusions and spore slink in the flax rust 
(plates 8, 9) - 113 
DopcGE, BERNARD O.  hatads of ice as he Oe adies a of the sete 
carp in certain species of the Ascobolaceae (plates 10-15) - - 139 
Howe, R. HEBER, Jr. The lichens of the Linnean Herbarium with as 
on Acharian material - - 199 
Evans, ALEXANDER W. diattone - Puerto Rico—XI olan 16, os - 209 
RoBINSON, WINIFRED J. A taxonomic study of the saaaliot costes of the 
Hawaiian Islands—I (plates 18-20) - - =" 927 
BRoapHuRST, JEAN. The genus shah id a its representatives in 
North America—I (plates 21, 22) - - 257 
LorENz, ANNIE. Vegetative reproduction in ae New Radand F ae 279 
Stosson, Marcaret. New ferns from Tropical America (plate 23)- - 285 
MACKENSEN, BERNARD. Three new species of oie with a discussion 
of the identity of Opuntia Lindheimeri = - - 289 
RYDBERG, PER AXEL. Studies on the Rocky Mountain fora—XXVI - 301 
Wi.uston, Ruta. Discoid gemmae in Radula - - 329 
Berry, Epwarp W. Notes on the genus Sp uidvinewsesne hie 24, 25)- 341 
- BrRoapuurst, JEAN. The genus crore and its aster in 
North America—II (plates 26-29) - - 357 
Berry, Epwarp W. Contributions to the Arar geek of i eile 
coastal plain—VIII. Texas (plates 30-32) - - - - - 387 
DARLING, CHESTER ARTHUR. Mitosis in living cells - - 407 
BICKNELL, EuGENE P. The ferns and flowering plants of tox 415 
ili 
