VOL 36 AUGUST, 1909 . HO. 8 



BULLETIN 



OF THE 



TORREY BOTANICAL CLUB 



€liitor 



MARSHALL AVERY HOWE 



John Hendley Barmhart Tracy Elliot Hazen 



h ■ 



Jean Broadhurst William Alphonso Murrill 



m 



Philip Dowell Charles Louis Pollard 



Alexander William Evans Herbert Maule Richards 



CONTENTS 



The western American birches BERTRAM T. BUTLER 421 



The ferns and flovsrering plants of Nantucket — V. EUGENE P. BICKNELL 441 



Notes on the effect of mechanical pressure on the roots of Vicia Faha. 



LOUISE HOYT GREGORY 457 



The genus Ceratopteris: a preliminary revision. * 



RALPH CURTISS BENEDICT 463 



Notes on Carex-V. KENNETH KENT MACKENZIE 477 



INDEX TO AMERICAN BOTANICAL LITERATURE^ 4^5 



PUBUSHED FOR THE CLUB 



THE NEW EBA PRINTING COMPANT 



Ip^NCASTCtt, PA. 



