Poly gala polygama and P. paiiciflora. 133 



from one end to the other ; a similar passage was observed by 

 Michaletin Viola alba." 



The surface of the ovary bears scattered, club-shaped, 

 glandular hairs, as seen in the figure. Their function is uncer- 

 tain, but it may be noted in advance that they are much more 

 numerous on the ovaries of the subterranean flower. Stomata 

 are sparingly present on the ovary. 



Gynceciuni. — B. In the aerial cleistogamic flower the pistil 

 presents a structure which is in a striking manner intermediate 

 between the chasmogamic and subterranean cleistogamic 

 flowers (Plate XVII, Fig. 2). The ovary is smaller than in the 

 former, the st>'le very much shorter, and the hairy tuft greatly 

 reduced, though it still forms a considerable outgrowth. The 

 glandular hairs on the surface of the ovary are rather more 

 abundant than in the preceding type of flower, although, as 

 will be seen later, by no means so profuse as in the under- 

 ground ones. 



Gynacium. — C. In the subterranean cleistogamic flower 

 the ovary is still smaller than in the last, the knob of the 

 stigma is much reduced in size, the tuft of hairs has almost 

 disappeared, and the style is reduced to the vanishing point 



(Fig. 3). 



The distal surface of the ovar>- is thickly covered with the 

 peculiar club-shaped glandular hairs already mentioned as 

 being present in the other types of flower. The contrast in 

 this respect with the ovary of the evident flowers is especially 

 striking. The glands are much more numerous, the cavit>' of 

 each is filled more richly with contents, and together they 

 form almost a complete coating. These glands are occa- 

 sionally found on the sepals. Nothing can be said positively 

 as to the function of these, but considering their rich develop- 

 ment, it must be that here we are dealing with advancing 

 specialization rather than degeneration. Two uses seem pos- 

 sible. They may serve in some way as absorptive organs. 



