SECTIONAL TRANSACTIONS.—C, D. MA 
15, Discussion on Metamorphism. Opener, Dr. J. S. Fuurr, O.B.E., 
F.R.S. 
In the afternoon an excursion took place to Green Collieries and 
Brick Pits in Coal Measures. 
SECTION D.—-ZOOLOGY. 
(For references to the publication elsewhere of communications entered in 
the following list of transactions, see p. 504.) 
. Thursday, September 13. 
7 1. Presidential Address by Prof. J. H. Asuworrs, F.R.S., on 
Modern Zoology: Some of its Developments and its Bearings on 
| Human Welfare. (See p. 108.) 
2. Prof. E. B. Pouuron, F.R.S.—The Meaning of the Transparent 
Under-surface of the Wings in Certain Butterflies. 
Mr. W. J. Kaye has recently shown that the dead-leaf-like under-surface of 
the Neotropical butterfly Protogonius is transparent, so that the upper surface 
alone is seen when the insect is sailing overhead. Although these butterflies 
have been known for 150 years, no one until the last few months has thought 
of holding a specimen up to the light! When the species, or more probably 
geographical races, of this genus are studied from various parts of tropical 
America, they are always found to resemble dead leaves on the under, and the 
dominant association of distasteful butterflies found in their locality on the 
upper surface. Everywhere this latter pattern is the one seen during flight 
and the leaf pattern only at rest with the wings closed. Mr. Kaye’s important 
discovery has suggested a new point of view in the study of insect patterns 
which has already led to many interesting and surprising results. 
3. Reports of Committees. (See pp. 318 seq.) 
4, Mr. J. T. Cunnincuam.—Origin of Adaptations: Present Position 
of the Question in relation to Recent Research. 
The novelty and interest of many recent discoveries have so absorbed the 
attention of biologists that the problems and the phenomena which occupied the 
minds of a former generation are in danger of being neglected and forgotten. 
The younger generation are apt to think that most, if not all, of the habits and 
deals of the Victorian era were merely the outward and visible signs of an 
rlier and less advanced stage of evolution. But just as from time to time the 
present generation finds it has to deal With the same problems of human life 
and society as had its parents and grandparents, so it is important for biologists 
to consider how far the new facts recently discovered help to explain the old 
phenomena and solve the old problems. 
Prof. Poulton, at a meeting of the Eugenics Society in July, described and 
showed lantern slides of some very extraordinary cases recently investigated of 
secondary sexual characters in male moths and caddis-flies. He described facts 
hich in his opinion showed that sexual selection actually occurs. Prof. 
Poulton was not in this case following any of the new doctrines, but upholding, 
as he thought. the original Darwinian theory. Yet he was forgetting the fact 
that the essential point in secondary sexual characters was their limitation in 
‘inheritance (not in heredity) to one sex, and that Darwin himself pointed out, 
his volume on ‘ Sexual Selection,’ that the selection would not bring about 
he difference between the sexes unless the variations selected were already 
H H 
