5C)2 



NATXJRE 



[Februairy 1 6, 191 1 



non-sexual nature of unicellular organisms — tacitly 

 assumed by the author — must be considered in an 

 analysis of this sort. The majority of Protozoa pre- 

 sent sexual phenomena in their life-histories, and 

 sexual processes also occur in many yeasts. Although 

 we believe that the Bacteria are truly non-sexual, we 

 think that the possibility of amphimictic processes 

 occurring in this group should at least have been 

 considered, as a certain amount of work has already 

 been published in this connection. 



C. Clifford Dobell. 



BIOCHEMISTRY OF FATS. 

 Monographs on Biochemistry. Edited by Prof. R. H. 

 Aders Plimmer and Dr. F. G. Hopkins, F.R.S. 

 The Fats. By Prof. J. B. Leathes. Pp. ix+ 138. 

 (London : Longmans, Green and Co., 1910.) Price 

 45. net. 



PROF. LEATHES 'S former book on the 

 " Problems of Metabolism " proved him to be 

 a writer with originality in his views and a capacity 

 for stating them in a lucid and convincing manner. 

 One therefore turned to his long-proinised monograph 

 on the fats with considerable interest, especially as 

 the subject is one to which he has devoted so much 

 experimental research work. 



The first hundred pages are devoted to a de- 

 scription of the chemistry of fats and their 

 constituents, and the various methods for separat- 

 ing, identifying, and analysing them. This sec- 

 tion of the book is useful and necessary ; the 

 facts, moreover, are clearly put and well arranged. 

 But this laying of the foundations affords little scope 

 for the thinker, and no doubt could have been equally 

 well done by any competent chemist. The real in- 

 terest of the book is the superstructure built upon 

 this, namely, the chapter on the physiology of the fats, 

 and one's only regret is that it occupies only eighteen 

 pages. Here the author is able to display his gift of 

 making the dark ways of metabolism as plain as is 

 possible with our present knowledge, and in suggest- 

 ing explanations and stimulating research on the 

 questions which are still largely hypothetical. 



One word of criticism of a quasi-adverse kind 

 appears to be necessary, and that relates to 

 what, after all, is not the most important 

 matter, namely, that of nomenclature. The Chemical 

 Society has laid down certain rules for nomen- 

 clature in order to ensure uniformity among 

 English-speaking chemists; such terminations as in, 

 ine, ol, ole, ase, &c., have definite meanings assigned 

 to them, and surely all writers should endeavour to 

 follow the laws put forward by the society, which 

 occupies the foremost place in the chemical world. 

 Prof. Leathes, however, speaks of lecithine, cere- 

 brone, nucleine, jecorine, &c., and the substance he 

 terms phlorrhizine is recognisable, though this spell- 

 ing does not occur so far as one knows in any other 

 English chemical book. 



He has also introduced an entirely new nomen- 

 clature for the principal lipoids, the phosphatides being 

 dubbed phophoHpines, the galactosides galactolipines, 

 and the basic constituents of galactosides lipines. 

 NO. 2155, VOL. 85] 



A new nomenclature is always sure to cause con- 

 fusion, especially among students, and so should never 

 be introduced without careful consideration and with 

 some prospect that it will at once "catch on," because 

 it is manifestly appropriate. Prof. Leathes has nt. 

 doubt very carefully considered his new terms, and 

 everyone will agree with him that the existing ter- 

 minology leaves much to be desired ; but it is very 

 doubtful whether his new terms are better than the 

 older provisional names. The chemical constitution 

 of most of the substances in question is still a matter 

 of doubt and speculation. The proper time to intro- 

 duce new names will be when their constitution is 

 fully known, and terms can then be framed which 

 will express their structure with accuracy. At present 

 Prof. Leathes has only introduced a new set of pro- 

 visional names, which, like the older ones, will dis- 

 appear when our knowledge is more exact. 



W. D. H. 



BIRD OBSERVATION. 

 Unleitung zur Beobachtung der Vogelwelt. By Dr. 

 Carl Zimmer. Pp. iv-l-134. (Leipzig: Quelle and 

 Mej'er, 1910.) Price 1.25 marks. 



THE author of this work is Dr. Zimmer, keeper 

 of the Royal Zoological Museum in Breslau. 

 On the first zoological excursion he undertook with 

 his pupils in the university of that town (where he is 

 also lecturer, as well as museum custos) they fell in 

 with a chaffinch singing in a tree. On his demanding 

 from them the name of the songster, the word 

 "nightingale" was ventured on after a prolonged 

 silence ! The little episode, which indicated, to his 

 surprise, their lamentable lack of knowledge of the 

 commonest local birds, induced Dr. Zimmer to prepare 

 this biichlein as an introduction to ornithological 

 observing. In some respects it reminds one of the 

 section in " Hints to Travellers," issued by the Royal 

 Geographical Society on the same subject, though 

 directed to a somewhat different class of observers. 

 One, however, lays the book down with the somewhat 

 unsatisfactory feeling that it is assumed that the stu- 

 dent will be made into an ornithologist by following the 

 instructions — all of them excellent and the result of 

 experience — therein contained, rather than that the 

 observer, who must be born so, and is already, if 

 that be his hent, an ornithologist, in embryo, before 

 he is aware of it, requires proper guiding only. 



Many of Dr. Zimmer's hints will assist in directin; 

 the young ornithologist's earlier methods, and sug- 

 gesting interesting lines of observation, and so will be 

 of considerable value. After some words of introduc- 

 tion, the author gives a list of helpful books on 

 ornithology, especially those with good illustrations, 

 in English as well as German. His next section 

 deals with the subject of excursions into " the open '' 

 in quest of birds in their wild state — " the study of 

 cage birds is a make-believe " — and the periods of the 

 day when they can be observed to most advantage. 

 The most suitable field-glasses for the purpose are 

 described. 



The larger portion of the book discusses bird life 

 at the different seasons of the year, and directs atten- ^ 



