2 SEPTEMBER 1911, Page 21

FIVE BOOKS FOR AMATEUR NATURALISTS.* PnorEssoa Anniurt THOMSON has added

a rather striking and, in one sense, a fairly original book to the long list of his published works. The Biology of the Seasons centres round an idea, familiar to naturalists, that the sun is the source of all mundane energy, and that the processes of life are rhythmic and punctuated by the seasons. Spring suggests of course buds, frog-spawn, caterpillars, and migration of birds ; summer means flowers, insects, the breeding of birds or mammals, and the play of young animals ; autumn is the season when seeds are scattered, leaves fall, earthworms are active, and salmon prepare to spawn. The biology of winter naturally suggests hibernation, the white coats of northern animals, the hoards of certain rodents, and, in the case of many organisms, death. All this sounds trite enough. But the merit of Professor Thomson is that he tries to explain what these things mean to the man of science. He is an evolu- tionist who recognizes that the living organism is a unity. Writing, as he does, with familiarity both with botany and zoology, he sometimes forgets how pro- foundly ignorant the ordinary person is of the fundamental

facts of biology. To such " protoplasm " is only a long word, while " angiosperm," " autonomic," and " ana- bolism" convey no definite meaning. A reference to the " otoliths of fishes " without explanation will represent nothing at all. But, apart from this occasional want of elementary clearness which the man of science writing in a popular fashion finds so difficult, there is a mass of varied and interest- ing matter in the book. The struggle for existence, the wastage of life, the plasticity of young animals and plants, the adaptation of organism to physical surroundings at the various seasons are touched on. Professor Thomson goes as deeply as possible into the problems and refers to the dis- coveries of a great variety of working biologists. The result is an extremely interesting book, though the chapters or essays rather lack connected unity. There are a dozen pretty coloured plates by Mr. William Smith—they would look better without the thick slate-coloured mounts.

We may also recommend to our readers a popular work on entomology. Our Insect Friends and Foes, by Mr. F. Martin Duncan, is written in an interesting fashion and gives a good deal of information on the habits and life history of a great variety of insects. The man of science may take exception to the inclusion of spiders, scorpions, and ticks, but Mr. Duncan is careful to explain in his first chapter that these animals differ from insects and are Arachnida. This introductory chapter gives a clear outline of the structure of typical insects and gives some hints on keeping them alive in aquaria or cages and studying their habits. There is no group of ubiquitous animals about which the patient amateur observer can add more to our knowledge. The classification given by Mr. Duncan is somewhat antiquated, and no entomologist will assent to the in- clusion of fleas with Diptera. They are now invariably placed in a separate order known as Siphonaptera or Aphaniptera. The second chapter is devoted to ants and bees and other insect communities. Aquatic insects, which are most attractive to watch in the confinement of an aquarium—which should be square and not a distorting globe—come next. Then mimicry and protective coloration, of which insects afford the most wonderful instances, are shortly treated. Silk, cochineal, lac, and cantharides provide matter for a chapter on insects in commerce. Insects and flowers merely touch the fringe of a subject that is botanical rather than entomological, and is partly made up of quotations from Anton Kerner. The last chapter is decidedly meagre and disappointing, but no one can deal with the vast subject of insects and disease in twenty pages. Fleas and plague are not even mentioned, and the Anopheles mosquito is disposed of in a few lines. Here Mr. Duncan has missed an opportunity of giving the general reader the result of much recent work. But though Mr. Dun- can tries to cover too much ground, and does so incompletely in several of his chapters, the general reader who wishes to learn something about the part played by insects may turn to

• (1) The Biology of the Seasons. By J. Arthur Thomson. Illustrated by William Smith. London Andrew Melrose. [1ps. 6d. net.]—(2) Our Insect .Friends and Foes. By F. Martin Duncan, F.B.P.S. With 54 illustrations from original photographs by the author. London Methuen and Co., Ltd. 16s.1— (3) Photography for Bird Losers: A Practical Guide. By Bentley Beetham, F.Z.S. With photographic plates. London: Witherby and Co. [5s. net.]— (4) Recreation icith a Pocket Lens. By W. James Wintle, F.Z.S. London : John Ouseley, Ltd. [2s. net.]—(5) Alpine Plants of Europe : together with Cultural Hints. By Harold Stuart Thompson, F.L.S. With 64 coloured plates OD figures). London : Geo. Boutledge and Sons. [Ps. 6d. net.]

this book. He will find it interesting and will acquire a deal of information for the most part trustworthy. The mis- prints in several Latin names might easily have been corrected. The book is well illustrated with small photographs.

We pass next to Photography for Bird Lovers. The name of Mr. Bentley Beetham is well known to ornithologists in this country. He is one of our most successful photographers. In this slender volume, which he calls " A Practical Guide," he gives a mass of information which will be invaluable to those who follow in his footsteps. The reader cannot but feel gratitude when an expert places his store of experience so unreservedly at the disposal of the public. The excellent plates in the volume are witnesses of Mr. Beetham's success. There are chapters on every branch of the art, from the choice of a camera and nest photography to stalking, cliff climbing, and photography of birds in flight. A couple of pages are devoted to cinematography. This is a book which will be indispensable to every one who turns to bird photography and is not too proud to profit by the numberless hints given by a capable instructor.

The nature of Mr. W. J. Wintle's Recreations with a Pocket Lens is sufficiently shown by its title. It is a small book written in an exceedingly chatty style. As a present for a youthful naturalist, together with a good lens, it may prove acceptable, and would open the eyes to much that is worth observation. But the youthful naturalist who expects to see with a pocket lens all that is shown in Mr. Wintle's illustra- tions will be woefully deceived. There are chapters on the choice of a lens and hints on the purchase of a microscope. Nearly thirty pages are wasted on the most useless and absurd " nature calendar " we have ever come across. Two entries will suffice : " April 1st : House sparrow building "; " April 22nd : Slugs are abundant."

Lastly we have Alpine Plants of Europe, which Mr. Harold Stuart Thompson, the author, tells us owes its origin to the fact that there is no well-illustrated book in English dealing with the whole range of the Alps. In this case Joseph Seboth's illustrations are utilized. Seven hundred species are described and 311 are figured. Mr. Thompson is a scientific botanist, and his book aims at giving fairly popular descrip- tions. But the absence of an analytical key and the fact that distinctions easily recognizable are not emphasized will prevent the hook being of as much service to the ordinary Alpine tourist as it might. The arrangement and classification adopted in the text is systematic, beginning with Ranunculacew and end- ing with eight Conifers. There are also a list of Swiss ferns and a glossary. It is a satisfaction to find a writer who aims at being popular recognizing the fact that "it is as easy to remember the universally used Latin names as it is to adopt ill-defined and unsatisfactory English ones.; The map at the end of the volume is uncoloured and the mountainous bits of country are not at all well shown. Besides the botanical descriptions there are notes on the geographical distribution of the plants and occasionally a few notes likely to be useful to cultivators of rock-gardens. We notice some plants included, e.g., Ranunculus checrophyllos, which under no conditions could be described as " Alpine." The excuse put forward is that they are useful for dry hot places in rock- gardens. The short introductory chapters on the nature of Alpine plants, their culture, and collection for the herbarium, are well done. Though there is much to be said for Mr. Thompson's book and for Seboth's little figures, the ideal " tourist's Alpine flora " remains to be written.