426 TOWER, DARWINISM. 
mentioned, with about 0.70 %, eliminated by predacious vertebrate 
enemies (0.694 °/,). In those eliminated by the vertebrate enemies, 
I was unable to detect any differences in pattern, form or any 
other aspect of the supposed resemblance to some model. I expected 
to find that the eliminated would, in general, consist of those which 
bore less resemblance to the model than did the surviving individuals. 
I was chagrined at these results, but there is no logical way of 
escaping the significance of the findings. The method employed 
left no loophole for interpretation. or explanation. 
The second aspect of protective resemblance, namely, whether 
these characteristics are actually utilized by the organisms posses- 
sing them as means of concealment, was attacked in another way. 
This consisted in following individual butterflies of species showing 
protective devices and recording their behavior, especially of certain 
species that resemble the East Indian Kallimas. The somewhat 
similar American types resemble Kallima in form, size and leaf-like 
markings on the ventral surface of the wings, of which so much 
has been made as a conspicuous case of protective resemblance. 
In 1906, while living in Orizaba, Mexico, I had opportunity to 
observe these butterflies closely in my own garden. This delightful 
tropical garden of two and a half acres, containing a great variety 
of plants, was a favorite haunt of these butterflies and also of a 
number of species of insectivorous birds. By following individual 
butterflies without disturbing them as they went about their daily 
occupations, I made records, sometimes over two hundred for an 
individual butterfly, of where he alighted after a short flight with 
reference to the use of his form and pattern as a means of con- 
cealment. It is obviously impossible in this paper to present the 
data in detail, but the general outcome of the entire set of obser- 
vations was that in 0.408 %, of the places where they came to rest 
from their flights would the protective resemblance be of any 
concealing use at all. Just over 50 %, (50.861 %) of their places of 
rest were brightly illuminated spots, where, instead of attempting 
to resemble a fallen leaf, they slowly opened and closed their 
wings, displaying the brilliant surface coloring, so that the combined 
motion and color made them highly conspicuous. I also found when 
one was chased and sought refuge from the predacious pursuit of 

