3'^ 



NA TURE 



[February i, 1900 



photographic lens makes us more than welcome Mr. 

 Dallmeyer's book, which, besides supplying a distinct 

 want, will be found a handsome and valuable addition 

 to any photographic library. W. J. S. L. 



NEW DATA FOR THE STUDY OF 

 VARfA TION. 

 Ueber eini^e Aberrationen von Papilio machaon. Von 

 Dr. J. W. Spengel, Professor der Zoologie in Giessen. 

 Pp. 48 Mit 3 Tafeln und 5 .A.bhildungen im Text. 

 (Jena: Gustav Fischer, 1899.) 



IT would be almost superfluous at the present time to 

 offer an apology for the intimate study of variation 

 in animals and plants. Evolutionists of whatever school 

 of thought must necessarily be agreed upon the import- 

 ance of variation as a factor in the production of new 

 forms, though they may differ widely as to the means by 

 which fresh species become established. In the present 

 state of evolutionary theory it is of the utmost conse- 

 quence to gain an insight into the laws which regulate 

 variation, and this can only be done by the accumulation 

 of accurate records of the results of experiment and 

 observation. Many views on the subject are current, not 

 one of which can be said to deserve mire than a pro- 

 visional acceptance, and all require to be rigorously tested 

 in the light of facts. Hence any competent observer 

 who— like Bateson, Standfuss, Merrifield and others — 

 devotes himself to laboriously collecting and carefully 

 recording data for the study of variation, whether natural 

 or artificial, deserves well of all those who are interested 

 in the progress of evolutionary theory. 



The present treatise is a useful contribution to the mass 

 of material that has lately been accumulating with refer- 

 ence to variation and aberration in the Lepidoptera. It 

 was long ago pointed out by Bates and Wallace, and 

 has often been insisted on since, that to the students of 

 evolutionary law the wings of butterflies afford an un- 

 usually favourable field of observation. The days are 

 gone by when the colour-patterns of insects were regarded 

 as mere elegant curiosities, with no particular bearing on 

 any question of scientific interest ; and when deviations 

 from the ordinary aspect of the species might be prized 

 indeed by the collector for their rarity, but were thought 

 to be beneath the notice of the genuine biologist. It is 

 now fully recognised in most quarters that there is no 

 real distinction to be drawn between "external charac- 

 ters '' and points of structure ; and, further, that while 

 both sets of features are equally under the control of 

 natural law, there are many principles of the first im- 

 portance whose operation is more clearly discerned and 

 more readily investigated in the former than in the latter. 

 During the .last few years much greater attention has 

 been directed to the phenomena presented by colour- 

 patterns than was previously the case ; and many ob- 

 servers, both in this country and abroad, among whom 

 may be reckoned Weismann, Eimer, Scudder, Mayer, 

 Haase and Piepers, have attempted, with more or less 

 success, to trace the history of existing patterns, and in 

 some cases to formulate the laws under which certain 

 changes of type have been brought about. 



The author of the communication before us has occu- 

 NO. 1579, VOL. 61] 



pied himself for many years with the study of natural 

 variation in the "swallow-tail" group of the genus 

 Papilio. The results of his investigation of over 2033 

 specimens still await publication ; but in the meantime 

 he has here put on record a very exact description of 

 several forms of the common swallow-tail {Papiluy 

 machaon)^ mainly from the collections of Staudinger, 

 Kratz, Standfuss and the Hon. W. Rothschild, which 

 come rather under the head of aberration than of or- 

 dinary variation. Some of these have been the result 

 of temperature-experiments, but the greater number have 

 occurred under normal conditions in the open. Dr. 

 Spengel makes no attempt to found any theoretical con- 

 siderations on the deviations they present, but restricts 

 himself to a statement of fact which, in point of fulness 

 and accuracy, contrasts very favourably with the hap- 

 hazard descriptions at one time thought sufificient. For 

 details, the reader must refer to the treatise itself ; but 

 we may here draw attention to the co-existence of 

 structural with colour-abnormality shown in the remark- 

 able aberration described on pp. 9-16. 



The figures are good, and greatly assist in the com- 

 prehension of the text. The authors system of nomen- 

 clature for the elements of the pattern is easily intel- 

 ligible, and may be followed without difficulty through 

 the pages of description. As a contribution to the stock 

 of material hitherto available, Dr. Spengel's treatise, 

 though limited in its scope, is of considerable value ; 

 and his further analysis of natural variation in allied 

 forms will be awaited with interest. F, A. D. 



OUR BOOK SHELF. 



A. Koelliker's Handbuch der Gewebelehre des Menschen 

 Sechste umgearbeitete Auflage. Dritter Band. Von 

 Victor V. Ebner. Erste Halfte. Verdauungs-organe, 

 Respirations-organe, &c. Pp. vi -I- 402. (Leipzig : W. 

 Engelmann, 1899.) 

 For the first time in its history the " Handbook of 

 Histology " of the famous Wiirzburg professor of anatomy 

 appears with the name of an editor upon its title-page 

 in place of the octogenarian master whose book, when 

 it first made its appearance in the 'forties, created an 

 epoch in the history of histological literature, and was 

 made familiar to English readers by its translation by 

 George Busk and Thomas Henry Huxley. The work 

 was a mine of original investigation, and served for many 

 years as a quarry which furnished the materials for the 

 building up of many an account of the structure of the 

 body, in which the source of information was too often, 

 it is to be feared, ignored. In later editions the general 

 style of the bock became somewhat altered, as it became 

 necessary for the author to refer to facts regarding micro- 

 scopic structure which were becoming added by others 

 as well as by himself ; and it must be admitted that, while 

 the book thereby accumulated a greater amount of inform- 

 ation, it became less readable and unquestionably less 

 original. Nevertheless, the parts of this last edition which 

 have already appeared have fully maintained the place 

 which V. KoUiker's "Gewebelehre" had taken as the first 

 authority upon the subject of which it treats. 



In Prof. V. Ebner's hands the character of the rest of 

 the work has been so maintained, and even the literary 

 style so closely imitated, that it would be difficult to 

 detect the alteration in authorship. The amount of 

 labour involved in producing a work of this kind can only 

 be roughly guessed at by those who have never them- 

 selves undertaken the task, and Prof. v. Ebner is to be 



