320 OBSERVATIONS ON PROTANDIU AND PROTOGYNY. 



The discharge of pollen in the bud must not be taken as a necessary 

 sign of self-fertilization. I have shown that this conclusion cannot be 

 drawn in the case of the Harebell; and the same remark will apply to 

 the Heaths. 



In Erica TeiraUx and cinerea, the pistil and stamens both arrive at 

 maturity before the opening of the flower, and yet apparently self-fer- 

 tilization does not take place. The pollen is discharged from terminal 

 pores directed inwards in close contact with the style, and can scarcely 

 reacb the stigma without artificial aid. Every one who is accustomed 

 to walk over heath-land must have noticed the small number of cap- 

 sules produced compared to the flowers. The fecundation which 

 does take place I believe is due to the small insects which enter 

 the bud through the little holes so constantly found pierced in the side 

 of the flower. In Chlora perfoliata, which is protogynous, and opens 

 only in bright sunshine, the stamens appear to approach the pistil suc- 

 cessively when the stigma is in a receptive condition, but before the 

 anthers are ready to burst. In Solatium Dulcamara the poUenis dis- 

 charged from terminal pores at a level not much more than halfway 

 up the style, in S. nigrum actually on to the stigma ; is either of these 

 species dimorphic? both are nearly synacmic. Plantago lanceolata, 

 the common Ribgrass, is one of the most striking common instances of 

 protogyny, the long awn-like stigma projects from the flower-bud long 

 before it opens, giving a comate appearance to the spike, and generally 

 withers up as soon as the anthers spring out on their long thread-like 

 filaments. In P. major the phenomenon is much less conspicuous, 

 while in P. media and maritima the stigma rather lags behind the 

 stamens than otherwise. In Scroplmlarinece, with the exception of the 

 very remarkable instance of protogyny in Scrophulazia aquatica already 

 described, synacmy appears to be the rule, not, however, I believe, 

 implying self-fertilization. In the Foxglove neither stigma nor sta- 

 mens are mature till the flower has been out some days, and is nearly 

 withering, and yet the number of pollen-tubes that pierce the style to 

 fertilize the almost innumerable ovules, must be prodigious. The 

 species of Labiala examined present, with the single exception of 

 Mentha Pulegium, uniformly strongly-marked instances of protandry. 

 The Marjoram is dimorphic, presenting one form with the stamens 

 longer than the pistil, in which the flowers are larger and of a darker 

 hue ; another form in which the pistil is longer than the stamens, and 



