386 



AUTOGAMY. 



pollen lying on the lowest perianth-leaf or with that still sticking to one or other 

 of the anthers (see fig. 311 *). 



Of the plants in which autogamy is brought about by inflection of the pedicel 

 combined with inflection or folding of the petals, two groups will be taken here as 

 representing two different forms of the phenomenon. These groups consist of the 

 Violacece of the Melanium tribe and the stemless Gentians. The manner in which 

 the pollen is transferred to the stigma in Violets through the agency of insects has 



2 



tr ^ 



Fig. 311.— Autogamy resulting from inflection of the peilicel combined with inclination of the style to the place where tlie 

 pollen has been deposited: Allium Chamcemoly. 



' Shows the aerial portions of the plant; nat. size. 2, 3, 4 single flowers with the front perianth-leaves removed; slightly 

 magnified. They are in the successive stages leading to autogamy. 



been already described on p. 280, and illustrated in figs. 279 



p. 279. The 



pollen thus deposited by insects on the slightly-projecting flap of the capitate 

 stigma is derived, of course, from other flowers, and the result of its transference is 

 a crossing between the flowers either of one or of two species. Autogamy is in 

 general scarcely possible in the Violet during the first part of the flowering-period. 

 If pollen is shaken out of the cone of anthers on to the proboscis of an insect which 

 is in the act of dusting the front surface of the stigmatic lobe with foreign pollen, 

 this new supply may, perhaps, be rubbed ofl" on to the back of the stigmatic lobe as 



