129 



well be given, showing how all the features of irregularity 

 acquired by the ordinary form must have been induced or 

 impressed upon the flower when growing laterally and easily 

 visited, but that they are readily lost as soon as the sap 

 can be distributed radially and so cause the parts to grow 

 symmetrically round the now vertical axis. 



Besides the occasional appearance of one or more terminal 

 and regular flowers among a truss of in^egular ones, it is the 

 object of florists to induce all the blossoms of many iiTcgular 

 flowers to become regular. Thus cultivated Pelargoniums, 

 Gloxinias, Azaleas, Pansies, etc., which are normally irre- 

 gular, tend to become regular under cultivation, and lose their 

 characteristic features. 



In all these cases I am inclined to recognize negative 

 evidence in favour of the theory advanced; in that, presuming 

 the characteristic irregularities to have been brought about 

 by the agency of insects and through the crossing of distinct 

 flowers by these creatures, and that the irregularities have 

 arisen under the various pressures, etc. ; then, under cultiva- 

 tion, though they may be repeatedly crossed by man — the 

 process, however, not being effected in the same way as by 

 insects, and consequently the causes of irregularity being 

 wanting — the flowers now revert to their ancestral forms; 

 while ample supplies of nutriment doubtless play an important 

 part in the process. 



Moreover, though any irregular flower may become regu- 

 lar, it is a significant fact that normally regular flowers are 

 never known to suddenly assume any definite irregular form. 



That the change from ii^egularity to regularity is an 

 acquired constitutional affection is seen in the fact that, 

 when the flowers of a drooping Gloxinia are fertilised with 

 their own pollen, a large number of the seedlings will bear 

 the erect regular form of flower. 



