iqiq] .STOrr— INTERSEXES II3 



eter, and all parts were then drawn to scale. Stamens and spores 

 were measured and drawn under higher magnifications. 



First form hermaphrodite (figs. 1-3, 49, 50). — This term 

 has been applied by Bartlett (2) to plants whose flowers very 

 uniformly show most complete development of stamens. The 

 filaments are usually twice as long as the pistils. The anthers 

 are large and well developed and white in color. In face view 

 when freshly dehisced (fig. 2) they measure about 2 mm. in length 

 by 1 . 5 mm. in width. The corolla lobes are well developed, with 

 blades strongly reflexed when anthesis is complete. 



The pollen of numerous plants of this form was examined 

 microscopically and rather extensive germination tests were made.' 

 Perfect grains are almost spherical, with thin smooth walls and 

 granular contents. There is much variation in the size of grains 

 that appear to be perfect, the smallest being about one-third the 

 diameter of the largest. There is also a considerable number of 

 obviously imperfect grains with shrunken shriveled walls that 

 are either empty or have hyaline contents. Such grains do not 

 swell up when placed in water or in various media used in testing 

 germination. Impotent grains frequently constitute 25 per cent 

 of the pollen of a microscopical mount. They have always been 

 found present to some extent. 



After a rather extended series of experiments it was 'found 

 that the pollen of this form germinates well in sugar-agar media. 

 The most uniformly favorable results were obtained with a 

 medium of 15 per cent sugar to which 3 per cent agar was added. 

 Good germination was also obtained in 15-1 and 15-5 solutions. 

 The largest tubes observed measured 3 . i mm. in length. Even 

 in the case of the most complete germination not all the spores 

 with granular contents germinated. No shriveled and hyaUne 

 spores germinated, but some of the smallest of the apparently 

 perfect spores germinated. Some granular spores of all the sizes 

 failed to germinate. A series of countings was made for a plant 



' In the various studies of the germinations of pollen reported in this paper the 

 writer has been assisted by Lieut. M. \'. Reed, a former student and scholar at the 

 New York Botanical Garden, and by Miss Helene M. Bo.as, laboratory assistant, 

 i6r whose efficient aid and cooperation acknowledgment is here made. 



