670 EXPERIMENT STATION EECORD. 



Concerning knowledge of nutrition and teaching of this subject in Bel- 

 gium, A. J. J. Yandevelde {Comiii. Rend. Com. rcnnanentr Beige Aliment. 

 Hummne, 2 {1910), i^p. 18-36; reprint, pp. 19). — In an address delivered before 

 the general assembly of the Belgian Permanent Commission of Human Nutri- 

 tion the author summarizes and discusses data regarding the present condition 

 of matters pertaining to the study of nutrition in Belgium. 



ANIMAL PRODUCTION. 



General biology, O. Hertwig (Allgcmeine Biologie. Jena, 1909, rev, ed., pp. 

 XIX+128, figs. 435). — ^A revised edition of a book previously noted (E. S. R., 

 IS, p. 651). New material has been added on Mendel's law, graft hybrids, 

 and other topics which have been the object of recent investigations. 



International catalogue of scientific literature, L — General biology {Inter- 

 nat. Cat. Sci. Lit., 6 {1909), pp. VIII+15J,; 7 {1909), pp. riII+1.58; 8 {1910), 

 pp. VIII+138). — This continues the subject and author catalogue of literature 

 relating to the study of the Individual cell and the metabolism, heredity, and 

 development of plants and animals previously noted (E. S. R., 20, p. 159). 



A laboratory text-book of embryology, C. S. Minot {PhHadelphi<i, 1910, 

 2. ed., rev., pp. XII +402, figs. 262). — A revised edition of a work designed 

 primarily for the use of students taking a practical laboratory course in 

 embryologj\ Besides covering the study of the chick, pig, and human embryos, 

 there are discussions on the vertebrate type, the theories of heredity, and 

 relatefl topics. The final chapter Is devoted to preparing embryos for the 

 detailed study of tissues. 



The physiology of reproduction, F. H. A. Marshall {London, New York, 

 and Calcutta, 1910, pp. XVII+106, figs. 154). — This comprehensive treatise on 

 the reproductive organs is intended primarily for biologists, gynecologists, 

 veterinarians, and animal breeders, and also to serve as a foundation for the 

 science of eugenics. The work is confined mainly to the physiology of genera- 

 tion among the higher forms, particularly the mammalia, but reproductive 

 processes of invertebrates are referred to whenever they throw light on the 

 more complex phenomena displayed by the higher animals. 



Chapters on fetal nutrition and the metabolism of pregnancy are written by 

 Dr. James Lochhead, and a section on the biochemistry of sexual organs by Dr. 

 William Cramer. 



Phases of evolution and heredity, D. B. Hart {London, 1910, pp. XI-\-259, 

 figs. 10). — A popular work on this topic, the special contribution of the author 

 being " an intrinsic theory of variation and its transmission," which " puts 

 A-ariation by environment or other causes quite out of the question." 



" The primitive germ cells which give rise to the gametes are derived from an 

 early division of the zygote, and travel through the organism to the sexual 

 gland without undergoing any mitosis, that is to say, without variation in their 

 structure. In the sexual gland they undergo mitosis, which means, as I have 

 already explained, variation in the determinants of the unit characters, accord- 

 ing to the law of probability. Probably two kinds of ova and spermatozoa are 

 formed then, but what division of unit characters Is in this way given is not 

 known [E. S. R., 22, p. 472]. When the gametes unite, we get half of the varied 

 chromosomes thrown off, and then when the zygote with its proper number of 

 chromosomes is formed, we get the phenomenon of Mendelism. by which the 

 unit characters are distributed in the zygote, again according to the law of 

 probability; so that by all this we get in subsequent generations organs follow- 

 ing the curve of probability in their anatomical condition and function. What 



