THE AMERICAN BOTANIST. 46 
bright sunlight, strong manures, or crossing increases the 
briUiancy of the flowers. From this point of view we can' 
understand why white flowers are most common in 
Nature, and why they are truest to name under cultiva- 
tion. Naturally florists find that they can develop any 
desired color variety from a white flower more easily than' 
from one already containing pigments. Individual white 
flowers not infrequently change to yellow, as in Lantanay 
or to red, as in Dianthus and Hibiscus mutahilis. 
There are only 257 red flowers in our northern flora.' 
They are most abundant in the pink family, or Caryo- 
phyllaceee, which contains 22 species. The pinks exhibit 
a wonderful variety of red shades varying through rose, 
pink and deep red to scarlet and crimson. The petals- 
may be dotted or marbled with w^hite, and they are often* 
notched or fringed, and surmounted with a corona of 
scales. The scent is aromatic and the honey lies at the" 
bottom of a long slender tube, where it is inaccessible to a 
great number of insects. The flowers are great favorites' 
with butterflies, and, therefore, it has been thought that; 
these insects prefer red coloring. But I am inclined to 
believe that it is largely the result of a coincidence that 
butterfly flowers are so often red-colored. For blue 
butterfly flowers do actually occur in Germany, while in' 
the pink family there are no blue flowers. Moreover 
butterflies visit most frequently of all the flat-topped 
clustered flowers of the Compositae, which afford them an 
excellent landing place, and I have found a much larger' 
number of them on the dull white clusters of the common' 
thoroughwort than on any other plant with which I am 
acquainted. Red flowers are also very common in the 
rose family, but there are no species which are adapted to 
butterflies. They are also numerous in the pea, mallow 
and heath families. Undoubtedly the two handsomest 
North American shrubs belong to the heath family. They 
are Rhododendron maximum and Kalmia latifolia or the 
mountain laurel. Asa Gray says that in North Carolina 
they adorn the valle^^s and mountains in immense abund- 
