308 NATURAL CROSS-FERTILIZATION IN INDIA. 



open flower the stigma is not visible, being always covered by the 

 stamens. In such flowers cross-pollination is almost impossible. 



Class II. Stamens about the same length as the style. 



This class includes the various conditions intermediate 

 between classes I and III, and comprises the majority of the types. 

 The stamens may be a very little longer than the style, so that 

 about half the anther projects above the stigma and the latter 

 in the opened flower is surrounded by the burst anthers, but is 

 not obscured by them as in class I. In other cases the tip of 

 the anther only may project above the stigma and the pollen 

 is deposited round its edge just before the corolla opens, while in 

 the fully open flower the empty anthers are clustered round the 

 style just below the stigma. In a few types the anthers may 

 just touch the stigma and the pollen is deposited at its extreme 

 edge or else beneath it. In such cases the anthers are sometimes 

 rather late in bursting and very little pollen is shed before the 

 flower opens. 



It is clear that very small differences in the length of the 

 stamens would produce any of these three conditions, and it is not 

 surprising to find that a certain amount of difference can sometimes 

 be found in the flowers of the same plant. For instance, in plants 

 where the anthers normally just touch the stigma, it is usual to 

 find some flowers in which they escape touching it. Thus, in some 

 flowers cross-pollination would be more favoured, in others self- 

 pollination. 



Class III. Style much longer than the stamens. 



This extreme condition in which the stigma grows out of tlie 

 unopened bud into the air, and in which self-pollination is exceed- 

 ingly difficult, was only met with in one case. In this type very few 

 capsules naturally set seed, and it was only possible to obtain 

 seed under bag by artificial selfing. 



These observations point to the likelihood of the frequent 

 occurrence, under Indian conditions, of natural cross-fertilization 

 in the field when the types are grown next to next. That natural 



