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whose "labours are devoted to the elucidation of the phenomena 

 of heredity and variation; in other words to the physiology of 

 descent." Further along the author expands this concept : "The 

 three aspects of the temporal changes of organisms, heredity, de- 

 velopment and evolution, are as intimately related as, for instances, 

 physiology and biochemistry among the sciences which deal with 

 the organisms as a going concern." The scope of the text is further 

 explicitly shown by its division into parts : ( 1 ) Formal genetics ; 

 (2) Genetics and development; (3) Genetics and evolution; (4) 

 Genetics and human affairs; (5) The nature of the gene. 



Such a text naturally presents distinct differences from one 

 designed primarily for "formal" genetics. The latter type of course 

 calls for the intensive study of a few fields ; the mastery of breed- 

 ing techniques, of mathematical calculations, and of cytological 

 data. A text in "genetics, evolution, and eugenics" must take into 

 account a wide survey of biology, together with consideration of 

 historical development as well. In the Waddington text, consider- 

 able parts are devoted to data from the fields of embryology, 

 systematics, geographic distribution, palaeontology, and to such 

 sociological aspects as population growth, dififerential birth rates, 

 sterilization, etc. 



Both the restricted and the broader types of genetics texts 

 have their values and supporters, and both meet demands ex- 

 pressed by college courses of these types. The broader type of 

 course is sometimes ofifered in sequence to a course in formal 

 genetics ; more frequently, it is independently given at more ele- 

 mentary levels of the curriculum. In such cases, it is sometimes 

 presented without laboratory work, as a "survey" or "correlation" 

 course. 



The Waddington text, however, is not intended for use in any 

 elementary grade of the college curriculum. Of about the same total 

 number of pages as the Sturtevant and Beadle, it has, because of 

 a larger page size and closer printing, at least fifty percent more 

 textual material. In its discussion of the cytological basis of in- 

 heritance, of mitosis and meiosis and chromosome behavior, it is as 

 recent as the other text and more extensive in detail. With an 

 appendix describing methods of culturing Drosophila, it is obvi- 

 ously intended that the text will be used in a course involving 

 formal laboratory work. While the discussion of evolutionary 



