— 184 
Professor PouLTON regretted to have to differ from two of bis 
American naturalist friends, but was somewhat consoled by the 
fact that they differed even more from each other. M. Abbott 
H. Thayer believed that the struggle for existence was so terribly 
severe that every Insect must be concealed, and he interpreted 
mimicry as the incidental likeness between species that were 
concealed in the same way. M. Schaus on the other hand 
doubted whether colours and patterns were of any service at all 
in the struggle for life. Between these two extremes the speaker 
said that be took a middle course. He believed that M Thayer 
was somewhat influenced in his views on warning colours and 
mimicry by the few examples of mimicry to be found in North 
America and that he would find it difficult to adjust these views to 
the multitude of well-established observations which are recorded 
from the tropics of America and Africa. 
Dr. F. A. Dixey remarked that there was no real antagonism 
between « field » and « cabinet » naturalists. Such observations as 
those of Mr. Schaus were of great value, and must be taken into 
account. But it did not seem to him that those observations were 
incompatible with the theories of Bates and Müller. 
In the case, for example, of the relative numbers of resembling 
species the facts recounted were easily explicable under the latter 
hypothesis, the difficulties in the way of common influence of 
external conditions appeared to him insurmountable. 
Mr. Marshall said the main difficulty raised had not been 
touched. Mr. Schaus asserted that Birds seldom attacked Butter¬ 
flies in flight, and never at rest. To this he could not agree; 
moreover, Mr. Schaus tells him that he has not read the recent 
literature on the subject. There are the cases of the Kestrel which 
took Butterflies at rest for hours, Fly-catchers in Ceylon ate 
damaged Butterflies on the ground, and no doubt many cases escape 
notice on account of the early 7 hour of Bird feeding. But there are 
three South American Birds which are known to feed largely 7 on 
Butterflies, while in Birma the nests of the Falcon have been found 
lined with debris of Insects, largely Butterflies’ wings. 
L’heure de la réunion au Musée royal d’Histoire naturelle étant 
proche, le Président lève la séance avant que la discussion ait pu 
être terminée. 
