5o8 



NATURE 



[March 30, 1893 



sanitary science. By placing in our hands a description 

 of the Public Health systems in vogue amongst con- 

 tinental nations, it allows us the opportunity of comparing 

 them with our own, and correcting our shortcomings by 

 their experiences. Notably should this be the case in 

 our methods of food inspection. H. Brock. 



OUR BOOK SHELF. 



The English Flower Garden : Style, Position^ and 

 Arrangement ; followed by a Description of all the best 

 Plants for it, their Culture and Arrangement. By W. 

 Robinson. Third Edition. (London : John Murray, 

 1893.) 

 This quite recently published new edition of this most 

 charmmg and useful book has been so completely altered 

 as to be at first sight scarcely recognisable, and we are 

 glad to record that all these alterations have been im- 

 provements, the result of a determination on the author's 

 part never to give up the effort of making it better. In 

 the present edition the old plates, many of which con- 

 tained but feeble portraits of plant life, have been broken 

 up, and in their places we find delightful pictures of some 

 of our best loved flowering shrubs and plants, at one time 

 represented as growing over walls or cottage porch, or 

 again by the lake or riverside. All of these are perhaps 

 not equal in execution, but it has seldom happened to us 

 to see so large a number of illustrations with so few that 

 are below a high standard. Such delightful woodcuts as 

 those of the double flowering hollyhock, the Alpine pink, 

 or oi Rodgersiapodophylla brighten up the pages and add 

 much of interest to this book. So familiar is this volume 

 to most lovers of plants, of which the fact of three editions 

 within ten years is a satisfactory proof, that it seems 

 almost needless to explain that the first portion of it is 

 devoted to a series of chapters on such subjects as design 

 and position of a garden, on the wild garden, the Alpine 

 garden, on spring, summer, and autumn flowers, and we 

 note even on *' Pergolas," the illustration of this latter 

 being from Venice. Alas ! in these northern countries 

 our sunshine scarcely ever needs a shade. The whole of 

 the first portion of the book is rewritten, and many new 

 illustrations are given, such as the " primrose garden in 

 a small clearing of a birch wood" in Surrey, the group of 

 " Solomon's seal at the foot of a wall," and others too 

 numerous to mention. 



The second and much larger portion is devoted to a 

 list, arranged in alphabetical order, of all those plants 

 that have been grown successfully in the gardens of Great 

 Britain and Ireland, and of some few that may be ex- 

 pected to grow there. Like the rest of the volume, this 

 part too has been very thoroughly revised and brought 

 up to date. To every one in the possession of a garden, 

 or having the care of one, we would say study this 

 " English Flower Garden," for you cannot do so without 

 profit. 



Logarithmic Tables. By Prof George William Jones. 



(London: Macmillan and Co., 1893.) 

 This book of tables, which we notice has reached its 

 fourth edition, will be found to serve the purpose for 

 many computations which require an accuracy extending 

 only to four or five, places of decimals. The tables 

 throughout seem to be well arranged, and the figures 

 neatly printed, thus fulfilling two important requirements 

 from the computer's standpoint. In addition to five- 

 place logarithms there is a table to four-places, together 

 with four-place trigonometric functions, a table of useful 

 constants, and an addition-subtraction table. Among 

 others we may mention a five- place table of natural sines, 

 &c., with a six-place table of their logarithms, prime I 



NO. 1222, VOL. 47] 



and composite numbers, squares, cubes, square roots, 

 &c., Bessel's coefficients for interpolation to the fifth 

 differences, binomial coefficients for interpolation, also 

 for fifth differences, and lastly a useful table of the errors 

 of observations, from v/hich we can at a glance determine 

 the ordinates of the probability curve, values of proba- 

 bility integrals, &c. An explanation, preceding the tables 

 themselves, shows how they may be adv mtageously 

 used, and the author offers the reward of " a dollar " for 

 the first notice of a mistake " to promote the detection of 

 errors." 



Catalogue of the British Echinoderms in the British 

 Museum {Natural History). By F. Jeffrey Bell, M.A. 

 (London : Printed by Order of the Trustees.) 

 During recent years many additions have been made 

 to the collection of echinoderms in the British Museum ; 

 and, as Dr. Giinther explains in his preface to the present 

 volume, much time and labour have been given to the 

 study and arrangement of these additions. It seemed 

 expedient, he says, to prepare, together with the nominal 

 list of the specimens, a complete account of the species 

 hitherto found in British seas. All students of the subject 

 will congratulate themselves on the fact that this decision 

 was arrived at, for the result is that they are now provided 

 with a handbook which will enable them to identify, 

 without much difficulty, any specimens that may come 

 in their way. Mr. Bell, in beginning the preparation of 

 so full a catalogue, had before him a task of no small 

 difficulty, and in the manner in which he has discharged 

 it he has displayed great patience, insight, and know- 

 ledge. A number of well-printed plates add largely to 

 the value of the work. 



LETTERS TO THE EDITOR. 



[ The Editor does not hold himself responsible for opinions ex • 

 pressed by his correspondents. Neither can he undertake 

 to return, or to correspond with the writers of, rejected 

 manuscripts intended for this or any other part of Nature. 

 No notice is taken of anonymous communications .^ 



The Hatching of a Peripatus Egg. 



In Nature, vol. xliv. p. 468, I briefly described some 

 eggs of the larger Victorian Peripatus, which were laid by 

 specimens kept alive by me in the winter (Australian) of 1891. 

 At that time, following previous authority, I identified the 

 species which laid the eggs as P. leuckartii. It appears now,, 

 however, that the real P. leuckartii— zX any rate, in New South 

 Wales — is undoubtedly viviparous, and our oviparous Victorian 

 species is, therefore, probably distinct. (It may be remembered 

 that in Nature, vol. xxxix. p. 366, I suggested this prob- 

 able distinction on account of the remarkable pattern of the 

 skin usually exhibited by the fifteen-iegged Victorian form.) 

 Further particulars on this subject are given in my "Further 

 Notes on the oviparity of the larger Victorian Peripatus, 

 generally known z.% P. leuckartii,'"'^ and in the literature cited 

 therein. In that paper I described two embryos, removed from 

 eggs which had been laid for about three and eight months re- 

 spectively. In the latter case I showed that the embryo was 

 possessed of the full number of appendages, and was in all re- 

 spects a perfect young Peripatus, differing externally from the 

 adult only in the smaller size and less deeply pigmented skin 

 On the strength of these observations I claimed to have definitely 

 proved that the larger Victorian Peripatus at any rate some- 

 times lays eggs, and that these eggs are capable of undergoing 

 development outside the body until perfect young animals are 

 produced. I am now able to add some further information. 



For some time only one egg (belonging to the original lot, for 

 none have since been obtained) remained in the hatching box. 

 The shell of this egg had changed to a dark brownish colour, 

 and latterly an embr)0 had been visible through the shell, coiled 

 up inside. The egg was lying on a small piece of rotten wood, 

 which rested on the glass floor of the hatching box. On 



1 " Proceedings of the Royal Society of Victoria," vol. v. p. 27 ; also- 

 Annah and Magazine of Nat-iiral Hist07y, i8g2. 



