PROBABLE REASON. 309 



trums, are generally yellow or white. The blue 

 delphiniums and aconites are highly specialised, 

 abnormal forms, and doubtless, therefore, of more recent 

 origin. Among the Caryophyllaceffi the red and pm'plish 

 species are amongst those with highly specialised 

 flowers, such as Dianthus and Saponaria, while the 

 simple open flowers, which more nearly represent the 

 ancestral type, such as Stellaria, Cerastium, &c., are 

 yellow and white. 



Take, again, the Primulaceae. The open-flowered, 

 honeyless species, such as Lysimachia and Trientalis, 

 are generally white or yellow ; while red, purple, and 

 blue occur principally in the highly specialised species 

 with tubular flowers. The genus Anagallis here, how- 

 ever, certainly forms an exception. 



Among the violets we find some yellow, some blue 

 species, and Miiller considers that the yellow is the 

 original colour. Viola hijlora, a small, comparatively 

 little specialised fly-flower, is yellow ; while the large, 

 long-spm'red V. calcarata, specially adapted to humble- 

 bees, is blue. In V. tricolor, again, the smaller 

 varieties are whitish-yellow ; the larger and more 

 highly developed, blue. Myosotis versicolor we know 

 is first yellow and then blue ; and, according to Miiller, 

 one variety of V. tricolor alpestris is yellow when it 

 first opens, and gradually becomes more and more blue. 

 En this case the individual flower repeats the phases 

 which in past times the ancestors have passed through. 



The only other family I will mention is that of the 



