180 HETEROSTYLED TRIMORPHIC PLANTS. Chap. IV. 



any fruit on this species. The stamens in some of 

 the flowers are partially converted into petals. Fritz 

 Miiller, after reading my description, hereafter to be 

 given, of the illegitimate offspring of various hetero- 

 styled species, suspects that these plants of Oxalis 

 may be the variable and sterile offspring of a single 

 form of some trimorphic species, perhaps accidentally 

 introduced into the district, which has since been 

 propagated asexually. It is probable that this kind 

 of propagation would be much aided by there being 

 no expenditure in the production of seed. 



Oxalis (Biophytum) sensitiva. — This plant is ranked 

 by many botanists as a distinct genus. Mr. Thwaites 

 sent me a number of flowers preserved in spirits from 

 Ceylon, and they are clearly trimorphic. The style 

 of the long-styled form is clothed with many scattered 

 hairs, both simple and glandular; such hairs are much 

 fewer on the style of the mid-styled, and quite ab- 

 sent from that of the short-styled form; so that this 

 plant resembles in this respect 0. Valdiviana and 

 Regnelli. Calling the length of the two lobes of 

 the stigma of the long-styled form 100, that of the 

 mid-styled is 141, and that of the short-styled 164. 

 In all other cases in which the stigma in this genus 

 differs in size in the three forms, the difference is of 

 a reversed nature, the stigma of the long-styled being 

 the largest, and that of the short-styled the smallest. 

 The diameter of the pollen-grains from the longest 

 stamens being represented by 100, those from the mid- 

 length stamens are 91, and those from the shortest 

 stamens 84 in diameter. This plant is remarkable, as 

 we shall see in the last chapter of this volume, by pro- 

 ducing long-styled, mid-styled, and short-styled cleisto- 

 gamic flowers. 



