;So 



NATURE 



[September 21, 1911 



stomach. This is a very tree translation of presure, 

 which really means rennet. Not having seen the book 

 in the original French, it is a little difficult to appor- 

 tion the blame between Dr. Gouraud and his trans- 

 lator. Internal evidence leads one, however, to 

 conclude that both are at fault. 



The book is a curious and muddled medley of fact 

 and fancy ; the translation has evidently been carried 

 out by someone unfamiliar with physiology, and de- 

 ficient in his knowledge of both French and English. 



W. D. H. 



OUR BOOK SHELF. 

 Lilies. By A. Grove. Pp. xi+116 + 8 coloured plates. 

 Apples and Pears. By G. Bunyard. Pp. xi+n6 + S 



coloured plates. 

 (Present-day Gardening Series.) (London and Edin- 

 burgh : T. C. and E. C. Jack, n.d.) Price is. 6d. 

 each. 

 Mr. Grove's book on lilies is one of the most welcome 

 that have appeared in this series. Among popular 

 flowers the genus is, perhaps, the most trying- with 

 which English gardeners have to deal, and the pre- 

 sence of many species in our gardens is due more to 

 the efficiency and rapidity of ocean transit than to a 

 proved capability of our cultivators to grow them in 

 gardens. It is probably to the facility with which 

 stocks can be renewed that the present unsatisfactory 

 state of lily cultivation is largely due. The incentive 

 to conquer the problems of keeping them alive and 

 propagating them are, to a great extent, lacking 

 when a new and vigorous stock can be easily ob- 

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 the genus — that he knows more about their cultiva- 

 tion than anyone else living. There is no botany in 

 the work; it is purely a gardening book cleverlv and 

 pleasantly written by a master of his subject. Mr. 

 Elwes contributes an interesting preface. 



Mr. Grove's study of lilies has been carried on 

 unostentatiously in his garden on the Berkshire hills, 

 and his name is comparatively unknown except to the 

 elite. It is otherwise with Mr. Bunyard. As the head 

 of one of the first fruit-tree nurseries, and an experi- 

 enced author on hardy fruits, he has long filled a 

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 of apples and pears. Although concise it is compre- 

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 better because they are comparatively short. He deals 

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 to t lie storing of the fruit. The state of many 

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 book may be widely read. 



Each of these volumes is illustrated by i sight 

 coloured plates, and makes a very creditable addition 

 to the useful series to which it belongs. 

 The Animal World. By Prof. F. W. Gamble, F.R.S. 

 With an Introduction by Sir Oliver Lodge, F.R.S. 

 (Home University Library of Modern Knowledge. ) 

 Pp. 255. (London: Williams and Norgate; New 

 York: Henry lloli and Co., n.d.) Price is. net. 

 Prof. Gamble's account of the animal world is 

 written from the point of view of function. Its chief 

 aim is to direct attention to the adaptations of struc- 

 ture to the performance of movement, breathing, and 

 NO. 2l86, VOL. 87] 



other vital functions. An introductory chapter, which 

 contains a general survey of the structure and classi- 

 fication of animals, is rather condensed, and will prob- 

 ably be more useful to the reader who has already a 

 little knowledge of animal life than to the beginner. 

 The description of the movements, and of the succes- 

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 colours and senses of animals, societies and associa- 

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 accounts of the life-history of a few animals, form the 

 subjects of successive chapters. The concluding 

 chapter on heredity and variation might well have 

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 for whom the book is intended. 



Several of the figures are crude, especially that of 

 Vorticella. The statement on p. 28 that the buds of 

 ceelenterates may remain in connection with the parent 

 tissues " by strings of mesenchyme " requires modifica- 

 tion. On' p. 37 the spaces between the mesenteries 

 of a sea-anemone are designated the ccelom, and 

 immediately below are referred to as increasing the 

 capacitv of the digestive cavity. 



The book, which is written in a fresh clear style, is 

 characterised throughout by breadth of view, and is 

 also noteworthv for the aptness of the illustrative ex- 

 amples cited. The thoughtful reader, with an interest 

 in biology, will find in this volume food for thought 

 in abundant measure. 



Orthochromatic Filters. Pp. 55. (Croydon : Wratten 



and Wainwright, Ltd., n.d.) Price 6d. 

 The title of this little book does not include its con- 

 tents, for there is a chapter on "contrast filters," 

 with some very striking examples of their use. A 

 photograph of an engineers' blue print taken through 

 a strong red filter that needs the exposure to be 

 increased twentv-four times with a Wratten 's panchro- 

 matic plate, renders the blue as a full black, instead 

 of the rather feeble grey given by an ordinary plate 

 with no filter. The great improvement obtainable 

 ir. the rendering of the grain of dark-coloured woods, 

 as well as in other cases, is well illustrated. We learn 

 that the sensitiveness to green and red of ordinary 

 orthochromatic plates is generally from 2 to 5 per 

 cent, of the total sensitiveness, while in a pan- 

 chromatic plate this rises to as much as 18 per cent. 

 From these and other figures of a like nature the 

 necessarv increase of exposure when using certain 

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 Many other matters are dealt with which are of prime 

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Studies oj Treesand Flowers. By M. Wrigley. With 

 descriptions by Annie L. Smith. Pp. 129 + viiiH- 

 i2o plates. (London : Methuen and Co., Ltd., n.d.) 

 Price 15s. net. 

 THE photographs that form the chief feature of this 

 weighty volume reflect considerable credit on the skill 

 ,il the author as a manipulator with the camera. Un- 

 doubtedly the most impressive are the photographs of 

 plants hi situ; the picture of the foxglove is good, 

 except thai it fails to show the lower portion of the 



