ACQUIRED REGULARITY AND " PELORIA." 131 



determines the persistent regularity of all flowers which are 

 normally so situated and are visited from all directions. 

 It will be often found that when Snapdragons have pelo- 

 rian blossoms they are in three-flowered cymes as in Cal- 

 ceolarias, instead of a raceme, of which the central one 

 is regular, while the lateral flowers are irregular. Secondly, 

 whether terminal or not, the influence which first brought 

 about the change in the anterior part of the flower spreads 

 to and effects all the rest. This statement, of course, only 

 expresses what one sees, without explaining the process ; 

 but the fact that the energy peculiar to the formation of one 

 organ can affect others is so common, that we may recognize 

 the process as a principle of growth ; just as stamens may 

 become petaloid, on the one hand, or pistiloid on the other ; 

 showing that " petaline energy " can affect the andrcecium 

 in the first case, and " pistiline energy " in the latter. 



That the true pelorian form is correlated to vegetative 

 energy is seen in the fact that such a flower obvionsly requires 

 more material than a normal one, and that petalody of the 

 stamens frequently accompanies the modification. Moreover, 

 although of course usually sterile under such cii-cum stances, 

 yet pelorian Linarias have been reproduced when the seeds 

 were sown in a rich soil. Mr. Darwin also raised sixteen 

 seedling plants of a pelorian variety of Antirrhinum artificially 

 fertilised by its own pollen, all of Avhich were as perfectly 

 pelorian as the parent plant. 



That peloria is due to hypertrophy is also seen in the fact 

 that it always arises by multiplication of the normally enlarged 

 organ. Thus, in Linaria and Antirrhinum all the petals are 

 spurred or pouched ; in pelorian Larkspurs and Aconites it 

 is the spurred and hooded sepal which is repeated ; and in 

 papilionaceous flowers it is the standard which is multiplied 

 five times, etc. An abnormal increase in the number of petals 



