DEGENERATION. 471 



membranous scales that represent leaves in Buscus, 

 Asparagus^ Pinus, &c. Similar productions are met 

 svitli within the flower, where they may occur as the 

 representatives of sepals, petals, stamens, or pistils, or 

 as mere excrescences. (See Enation.) Whole families 

 of plants, e. g. Sapindacece^ are characterised by the 

 presence of these organs, which are often of great 

 interest to the morphologist as indicating the true 

 symmetry of the flower, while they have acquired fresh 

 importance since the publication of Mr. Darwin's work 

 on the ' Origin of Species,' wherein we are taught to 

 regard these rudiments as, in many cases, vestiges of 

 organs that were more completely developed in the 

 progenitors of the present race of plants, and the 

 exercise of whose functions, from some cause or other, 

 having been rendered impossible, the structures become, 

 in process of time, proportionately stunted. 



Thus, in dioecious plants we frequently find traces 

 of stamens in the female flowers, and rudiments of the 

 pistn in the male flower, indicating, according to the 

 Darwinian hypothesis, that the ancestors of these 

 plants were hermaphrodite (see Heterogamy). 



Mr. Darwin has also shown that, in some cases, the 

 utmost degree of fertihty is attained, not from the 

 action of the pollen on the stigma of the same flower, 

 but on the influence of the male element of one blossom 

 upon the female organs of another flower on another 

 individual plant. 



Hence, in such plants there is a tendency to a sepa- 

 ration of the sexes, while, from what has been before 

 stated, i might be expected that rudiments of the 

 male or female organs would be found, and also as a 

 result of the operation of the law of inheritance. On 

 the same principles it is easy to understand the occa- 

 sional presence of the perfect in place of the rudimen- 

 tary organs, as in Dianthiis. 



In some instances the assumption of a scale-like 

 form by any organ is attended by a change in texture, 

 the organs becoming dry and scarious, or fleshy. 



