Caryophyllaceæ. 289 



the styles were bending backwards so decidedly that they 

 almost touched the petals and were more-or-less dipping 

 into the pollen, so that self-pollination took place. 



In one flower the styles were only slightly curved back- 

 wards, but were already covered with germinating pollen; 

 of the anthers, only the cal.-anth. were open and had shed 

 a little pollen. Here, consequently, a slight degree of proto- 

 gyny, if anything, appears to have taken place. 



Switzerland: Protandry, with ultimate self-pollination (H.M.). 



4. Cerastium trigynum Vill. (Fig. 27). 

 (= Stellaria cerastoides L.) 



Greenland: Gynodioecism with decidedly homogamous 

 or slightly protandrous or slightly protogynous flowers, g 

 but rarely $; gynomonoecism rare. Self-pollination. 



Ç. The petals are only slightly outspread (Fig. 27, A) 

 so that the flower becomes on the whole, bell-shaped; but 

 it is possible that light and heat exercise some influence as 

 regards this point. The flower is not infrequently somewhat 

 irregular, some of the petals being smaller than the others. 

 The petals grow decidedly during the flowering period; they 

 are 6 — 10 mm long, but vary in length relatively to the 

 sepals. The anthers and the stigmas attain almost the same 

 height and are functional at the same time ; as all the stamens 

 simultaneously stand erect closely around the pistil, and 

 the styles are more or less outwardly curved, self-pollination 

 is inevitable (Fig. 27, B)^ and the numerous pollen-grains 

 which are sometimes seen upon the styles (Fig. C) are also 

 indicative of this; contact has also been directly observed 

 (Fig. B). In fully developed buds the anthers are quite ripe, 

 and they often dehisce immediately after the bud has been 

 artificially opened; I have even found them dehisced in the 

 bud itself, and as the stigmas also are fully developed, I 



