324 Schively — Contributions to the Life History of 



of hairs having gradually assumed the characteristic 

 appearance. The early condition of style and stigma is 

 seen in Plate XXXI., Fig. 8, and the later one in Fig. 9. 

 These drawings are made to the same scale. 



Fertilization. 



It will be seen from the previous description of the struc- 

 ture of Amphicarp&a that the purple flowers are well pro- 

 vided with those devices which are associated with insect 

 fertilization. It is probable that this is not the method 

 here, though there are strong grounds for believing that 

 the plant may be a descendant of types that were insect- 

 pollinated. If insects visit these flowers, the writer has not 

 seen them, nor has any indication of such visitors been 

 discovered. 



As has already been stated, in the tiny bud, not more 

 than one-quarter of an inch in length, the style has already 

 grown some distance beyond the stamens, and curves the 

 stigma toward them. After this both stamens and pistil 

 elongate and finally are about the same length, the stigma 

 protruding a short distance beyond the anthers. Upon 

 opening a bud about a half inch long, but that is still 

 closed, it will be found that the anthers have dehisced, and 

 usually some pollen is found upon the stigma. 



It is quite certain that the majority of the purple flowers 

 do not produce fruit; a number, however, are productive. 

 Perhaps the stigma is not in condition when the pollen is 

 mature. Should this be the case, the question naturally 

 arises, how is fertilization accomplished in any case? For 

 the present it can only be stated that it is possible that the 

 ten stamens may reach maturity at different times. It is 

 also suspected that there may be some explanation yet to 

 be discovered in the long-continued curving of the style 

 towards the stamens. 



