226 THE STKUCTURE OF FLOWERS. 



only we must always remember that there may be a variety 

 of causes which may equally well bring about the same 

 result. 



It may be also borne in mind here that another result 

 of low temperature is, while retaining the function of the 

 androecium, to arrest the expansion of the corolla and to 

 render the flowers self-fertilising. This is peculiarly the 

 case with the Alsinece ; while Laviium amplexicaule fails to 

 open its earliest small-flowered flowers at all, being strictly 

 cleistogamous. 



The preceding cases of gynodioecism are all associated 

 with a more or less degree of protandry. It is rarer to find 

 it accompanied with protogyny in the hermaphrodite form. 

 Miiller records it in Plantago lanceolata in England, which I 

 can corroborate, and in P. media in Germany. These plants 

 are aneraophilous, and in a state of passage from an ento- 

 mophilous ancestry ; so that it may have been retained from 

 an early condition. 



Gynomonoecism is not particularly common, except in the 

 Gompositce., where the ray florets are often female, while 

 the disk florets are hermaphrodite. This is due to com- 

 pensation ; for transitional states may be seen in flowers 

 which are passing into the "double" condition; for as the 

 corolla changes its form and becomes ligulate, the stamens 

 are sup23ressed, and the style arms alter their shape. 

 Anemone hepatica is said to be gynomoncBcious,* and also 

 Syringa Persica.f I have seen no case, and no description is 

 given of these two, so that I can only suggest that it may 

 be a result from degeneracy, perhaps on the road to a 

 petaloid condition of the stamens. Such a state I have 

 found in a Plantago which was gvnodioecious. 



* Dr. S. Calloni, Arch. 8ci. Phys. et Nat., xiii., 1885, p. 409. 

 t Miiller, Fertilisation, etc., p. 393. 



