Book Description

Excerpt from The Entomologist, 1891, Vol. 24I AM surprised to find that Mr. Cockerell should have found it necessary to defend the views he put forward in a former paper (entom. Xxii. 177 as to the possibility of the sex being determined in the embryo by external influences, especially food. The hypothesis is now very generally accepted by biologists in relation to animals in general, and may be found stated very clearly and fully in a most interesting volume of the International Science Series, The Evolution of Sex, ' by Profs. Geddes and Thomson. Mr. Wailly will find in Chap. IV. A reference to Lepidoptera, Mrs. Trent's experiments and Mr. Gentry's Opinion being cited. A very stron case is made out in favour of the contention that difl'erences 0 nutrition, in conjunction with other conditions of environment (chiefly bearing on assimilation probably) in the larval or embryonic state, determine the sexual distinctions. Evidence bearing on the subject is adduced from the life-history of the tadpole, bee, aphis, and certain arthropods. I think most practical entomologists' experience will, in a more or less degree, bear out the theory. I venture to note one or two observations of my own. I have observed in the South of France and in Italy the dwarfing of L. Icam and astrarche, resulting from the stunted condition of the food-t produced by the climate and dry soil, and not the less striking is the preponderance of males over females in such localities.About the PublisherForgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.comThis book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.