NOTES AND OBSERVATIONS. 159 



green, one margin of each segment 



more 



tint. The lower half of the broad tube is obtusely 5- 

 sided, and the tube is widest at about the middle. 



While the stamens are all inserted on the lower part of 

 the corolla tube, those opposite the lobes have their fila- 

 ments broadly dilated at this point, below which they 

 appear as mere lines on the inner side of the corolla, while 

 the alternate ones are compressed from the sides above 

 their insertion, below which they extend to the receptacle 

 as prominent ridges closely applied to the grooves which 

 separate the five pistils. At their insertion, the filaments 

 are strongly bearded. On the back of each pistil, near its 

 base, is a yellow cup-shaped nectary, forming a pocket 

 covered by the fleecy nectar guard, and separated from its 

 fellows by the decurrent filament ridges already described. 

 All of the filaments converge to the center of the flower 

 just above their insertion, where they lie closely applied to 

 the pistils, with which they protrude for a short distance, 

 their ends being slightly divergent, so as to remove the 

 thin cordate anthers a short distance from the minute 

 terminal green stigmas. These become moist and receptive 

 only after the anthers have shed their pollen, thus insuring 

 a probability of cross-fertilization by aid of visitors attracted 

 by the nectar secreted in the pockets on the backs of the 

 pistils and protected by the tufts of hairs at the base of 



the stamens. 



An interesting feature of the stamens is the changes 

 which the anthers undergo during anthesis. When the 



&" — * — © 



olla 



© 



are narrowly oblong, the 



connective tipped with a small glossy gland ; but in dehis- 

 cing they contract to a broad heart shape, expelling the 

 pollen in long worm-like threads which are held by one 

 end until brushed away. 



form 



more recurved margins 



varieties 



