Perhaps we shall find out the reason for some of these things. But naturalists have known the houses of oak-insects for two hundred years now, and if they haven't found the answers to some of these questions yet, perhaps no one ever can. But that isn't a good way to look at Nature. And so Mary and I don't. We think we may make a great discovery any day. We are like prospectors in the gold mountains. We never give up; we always keep prying and peering. The worst of it is, I suppose you think, that we always keep talking too. Well, this is the last sentence of this dose of talking; or next to last. For this is the END of this rambling, talky, little book. * * * * * BY THE SAME AUTHOR ELEMENTARY ZOOLOGY Pp. xv+492, 172 figs., 12mo, 1901, $1.20 FIRST LESSONS IN ZOOLOGY Pp. x+363, 257 figs., 12mo, 1903, $1.15 AMERICAN INSECTS Pp. vii+671, 812 figs., 11 colored plates, 8vo, 1905 (_American Nature Series, Group I_), $5.00. Students' edition, $4.00 DARWINISM TO-DAY Pp. xii+403, 8vo, 1907, $2.00 HENRY HOLT AND COMPANY PUBLISHERS NEW YORK * * * * * THE AMERICAN NATURE SERIES In the hope of doing something toward furnishing a series where the nature-lover can surely find a readable book of high authority, the publishers of the American Science Series have begun the publication of the American Nature Series. It is the intention that in its own way, the new series shall stand on a par with its famous predecessor. The primary object of the new series is to answer questions which the contemplation of Nature is constantly arousing in the mind of the unscientific intelligent person. But a collateral object will be to give some intelligent notion of the "causes of things." While the coöperation of foreign scholars will not be declined, the books will be under the guarantee of American experts, and generally from the American point of view; and where material crowds space, preference will be given to American facts over others of not more than equal interest. The series will be in six divisions: I. NATURAL HISTORY This division will consist of two sections. =Section A. A large popular Natural History= in several volumes, with the topics treated in due proportion, by authors of unquestioned authority. 8vo. 7-1/2x10-1/4 in. The books so far publisht in this section are: =FISHES=, by DAVID STARR JORDAN, President of the Leland Stanford Junior University. $6.00 net; carriage extra. =AMERICAN INSECTS=, by VERNON L. KELLOGG, Professor in the Leland Stanford Junior University. $5.00 net; carriage extra. Arranged for are: =SEEDLESS PLANTS=, by GEORGE T. MOORE, Head of Department of Botany, Marine Biological Laboratory, assisted by other specialists.