210 THE AMERICAN NATURALIST. [Vor. XXXV. 
attract many butterflies. The handsome red flowers of Sapo- 
naria ocymoides are very abundant on sunny slopes in sub- 
alpine regions and are sought by twenty-eight species of 
butterflies. The species of Dianthus have the calyx tube so 
long and narrow that the honey can be reached only by 
Lepidoptera. The flowers are rose or dark red, elegantly 
marked, of large size and great beauty. The association of 
bright red coloration with a slender calycine tube and fertiliza- 
tion by butterflies is not a coincidence, for throughout the 
Caryophyllacez in proportion as the flowers increase in 
conspicuousness the power of self-fertilization is lost. 
* As the honey gets more deeply concealed and access more 
directly limited to butterflies, we find," says Müller, “pari 
passu among the Caryophyllacez increasing development of 
sweet scents, bright red colors, fine markings round the 
entrance of the flower, and indentations at the circumference. 
All these characters which are so attractive to us seem to have 
been produced by the similar tastes of butterflies.” This view 
is much strengthened when it is considered that the nocturnal 
flowers of the genera are white, and without variegation. 
Saponaria officinalis is pale pink, or, on expanding, white, with 
the perfume strongest in the evening; Sz/ene nutans, S. nocti- 
Jora, and Lychnis alba all have white or pale pink flowers and 
are visited by night-flying Lepidoptera. Since red is invisible 
at night, while white is conspicuous, it is evident that the 
former color would be disadvantageous to nocturnal flowers. 
Originally the flowers of these genera were probably pale pink 
or whitish, as in Gypsophila, where they are small, reddish, the 
tube short, the honey fully exposed, and the visitors a miscella- 
neous company of flies, bees, and Lepidoptera. A part of 
the species became adapted to butterflies and a part to moths ; 
no new colors were developed, but the red and white were dif- 
ferentiated. The sexual markings of butterflies show that they 
are in a very high degree color-loving insects, and while they 
visit flowers of all colors they certainly prefer bright hues to 
dull, and as with rare exceptions butterfly flowers are red, it is 
probable that they find this color most attractive. 
Under cultivation the pinks have proved susceptible of great 
