120 



A NOTE ON THE VITALITY OF THE SPORES OF 



MARSILEA * 



By Marshall A. Howe 



In 1888, Professor D. H. Campbell f alluded to the germi- 

 nation of spores of Marsilea Acgyptiaca, " in some cases twelve 

 years old." The material with which he worked had been pre- 

 served in a dry condition in the Botanical Museum of Berlin, 

 and the spores germinated within thirteen hours after being 

 placed in water. In the course of some remarks on this subject 

 before the Cleveland meeting of the Botanical Club of the Amer- 

 ican Association for the Advancement of Science, Professor 

 Campbell is reported J to have said that of spores eleven years 

 old, fifty per cent, germinated, and of those five years old, 

 almost all grew. In the Botanical Gazette for 1895 (20: 229), 

 Professor Barnes recorded a still more surprising instance of 

 retention of vitality in the case of the spores of Marsilea quadri- 

 folia, which germinated after the sporocarps had been kept con- 

 tinuously for three years in commercial alcohol (95%), the 

 natural inference being that the exceedingly hard wall of the 

 sporocarp is so compact as to resist successfully the penetrating 

 powers of strong alcohol for a period of three years at least. 



In May, 1900, for use in a course of laboratory instruction in 

 Columbia University, three or four sporocarps were taken by 

 the writer from an herbarium specimen of Marsilea qitadrifolia 

 collected by L. M. Underwood and C. R. Barnes, on June 13, 

 1 891, in Fresh Pond, near Cambridge, Mass. (whence, also, the 

 specimens preserved in alcohol by Professor Barnes came). 

 These sporocarps were placed in water after a small portion of 

 the wall of each had been cut away in order to give the water 

 a better chance to penetrate, and they soon burst open, emitting 

 the long gelatinous ring and the attached sori in the way figured 



* Read before Section G of the American Association for the Advancement of 

 Science, Pittsburg, July 3, 1902. 



| Bull. Torrey Club, 15: 259. O. 1888; Berichte Deutsch. Bot. Gesellsch. 6: 

 340. 1888. 



% Bot. Gaz. 13 : 235. S. 1888. 



