September 30, 19 10 J 



SCIENCE 



429 



Fonscolombe, Say, Eambur, Hagen, de Selys 

 and the others ! All this might be thrown 

 away, were there any compensating gain, but 

 so far as I can see, there is only loss. It is 

 not easier to remember numbers than names ; 

 on the contrary, they are much more readily 

 forgotten, transposed or misprinted, and when 

 mixed up they contain no clue to enable us to 

 set them right. 



I have worked many years at different 

 branches of zoology and botany, and venture 

 to affirm that it is easier to remember names 

 than species. The names which come before 

 us as a chaotic multitude, menacing and in- 

 comprehensible, are those of things we do not 

 Icnow. To me, even these names have a sort 

 of charm, like that of unknown people passing 

 in the street, each one a little mystery, with 

 wonderful if unknown history and meaning. 

 A high degree of complexity in nomenclature 

 is reached when we attempt to indicate all 

 sorts of minor categories, subgenera, subspe- 

 cies and the like, but all this is for the pur- 

 pose of reflecting in some poor way the real 

 complexity of nature. The mind can not 

 grasp it all, but it is possible to attain a 

 reasonable comprehension of parts, and for 

 this it seems to me that nomenclature (not 

 numeration) is a useful tool. I am the more 

 convinced that we are on the whole doing well, 

 from the fact that in practically every group 

 which I have studied, the path of the student 

 is far easier to-day than it was twenty years 



ago. T. D. A. COCKERELL 



Univeesity of Colorado 



SCIENTIFIC BOOKS 

 Studien ueher die Bestimmung des weihlichen 



Geschlechtes. Dr. Achille Eusso. Pp. 



iv + 105 ; 32 figures. Jena, Gustav Kseher. 



1909. 



In this brochure Professor Russo, of the 

 Imperial University of Catania, has presented 

 in German a compilation of the results that 

 he has already announced in Italian publica- 

 tions, together with abstracts of more recent 

 and unpublished work. The title of the pres- 

 ent paper would indicate that its author has 

 dealt only with the determination of the fe- 



male sex, but as a matter of fact he outlines a 

 series of experiments designed to show that 

 sex is a question of maternal metabolism and 

 that Mendelian dominance is similarly de- 

 pendent upon conditions of nutrition in the 

 mother. It is apparent, therefore, that the con- 

 clusions of Professor Russo upon the subjects 

 of sex determination and Mendelian inherit- 

 ance are widely at variance with those held by 

 the majority of his fellow workers in these 

 lines of investigation. Should he be found 

 correct, much of the work of cytologists and 

 experimental breeders of the last ten years is 

 seriously in error. For this reason his data 

 should be carefully considered in order to de- 

 termine whether he is justified in opposing the 

 prevailing opinions regarding the subjects he 

 discusses. 



The material is presented under three head- 

 ings : I., General Part, wherein the author 

 gives his conclusions and a summary of his 

 results; II., Analytical Part, in which is con- 

 sidered the function of the epithelium of the 

 rabbit ovary and the experimental proof to 

 show that this is under control by artificial 

 means; III., Experimental Part, where the 

 results of the breeding trials are given and 

 criticisms of the work of other investigators 

 following his methods are presented. The 

 line of reasoning pursued by Professor Russo 

 is, in brief, this : Sex and the characters of the 

 soma in the offspring, at least so far as pig- 

 mentation is concerned, are the result of the 

 metabolism in the mother at the time the eggs 

 are produced and made ready for fertilization. 

 The maternal condition impresses itself upon 

 the egg through the medium of the epithelium 

 of the ovary. Preponderant anabolism re- 

 sults in the production of large proportions of 

 females, while the opposite condition favors 

 the production of males. Likewise favorable 

 conditions of nutrition in the mother reverse 

 the factors of dominance in Mendelian in- 

 heritance. So far as the matter of sex deter- 

 mination is concerned it is apparent that we 

 have here a revival of the epigamous theory 

 so thoroughly and ably presented by Geddes 

 and Thompson. The modification of Men- 

 delian characters is, however, something en- 



