ENGELMANN THE FLOWERING OF AGAVE SHAWII. 581 



On the 2nd day the anthers are shrivelled, though quantities of 

 pollen remain adhering to them ; the perigon withers more ; the 

 style in the morning is still shorter than the filaments, but in the 

 evening has exceeded their length somewhat; the stigmatic lobes 

 remain entirely closed. 



On the 3rd day these changes go on gradually and slowly. 



(Fig. 7-) 



On the 4th the style is 3 inches onger than the perigon, the 

 lobes of which are wilted and twisted, while the filaments also 

 wither; in the evening the stigmatic lobes begin to separate and 

 exude some moisture. The color of the flower, which at first was 

 greenish and sulphur-yellow, now is of a deeper dirty vellow. 



On the 5th day the style has reached its full development. 2k— 

 zj inches longer than the wilted perigon ; the filaments are droop- 

 ing, the anthers shrivelled, much pollen yet adhering to them ; 

 the stigmatic lobes have separated and are covered with a large 

 drop of sweet, glutinous stigmatic liquid, which causes the pollen 

 grains that drop into it to developc their long tubes (Fig. 8). 



The drop of stigmatic fluid remains I'resh and full for another 

 and often even a third day, and then gradually dries up ; the func- 

 tions of the flower are ended wi h the fertilization of the ovules.* 



I have not yet made mention of the abundant secretion from 

 the nectariferous lower part (all the part below the insertion of 

 the stamens) of the perigonial tube. During the several days in 

 which the flowers were open the whole tube was filled to the brim 

 with a sweetish watery liquid, of a slightly nauseous odor. I am 

 not aware that such a secretion has before been observed in Agave 

 flowers, and would now consider it as an abnormal phenomenon, 

 originating under artificial circumstances, had not others, whose 

 attention I had directed to such secretion, noticed the same in 

 other species. Prof. C. S. Sargent, of Cambridge, Mass., saw it 

 in an A. yucccefoUa which bloomed there last winter under glass, 

 but could not find it in two specimens of the same species which 

 in September flowered in the open air. Of greater importance, 

 because made on a wild plant on its native mountains, is the 

 observation of the Rev. E. L. Greene, who found last summer in 



* Buds or flowers that are kept for a while separated from the plant such e.g. as are sent 

 fresh by mail, become distorted, the ovary swells, the style lengthens, but the perigon and 

 stamens wither even if not yet fully developed. 



