84 GENETICS [BoT. Absts., Vol. X, 



allelomorphic pairs and 2 series of multiple allelomorphs. Two of the 4 are also involved in 

 development of aleurone color. One pair of allelomorphs is linked with yellow endosperm and 

 1 series of allelomorphs with liguleless leaf. — R. A. Emerson. 



529. Fairchild, David. Visible records of heredity. Jour. Heredity 12: 174-176. 

 1921. — A plea is made for greater use of photography in recording results of genetic researches, 

 with suggestions for more adequately and properly photographing new forms produced in 

 breeding experiments. — C. B. Hutchison. 



530. GuTHERZ, S. VON. Geschlecht und Zellstruktur. [Sex and cell structure.] Natur- 

 wissenschaften 8: 878-888. 1920. — The author presents data taken from the work of others 

 on the question of the relation between sex and cell structure. He discusses in some detail 

 digametic sexes in unisexual organisms, also morphological and physiological aspects of sex 

 chromosomes. Conclusions derived from his investigations on the spermatogenesis in the 

 white mouse are as follows : (1) Spermatogenic development proceeds in rhythmic series; (2) 

 an intra-nuclear basic-staining body looked upon as a heterochromosome is manifest between 

 the middle and end of the spermatocyte period; (3) the heterochromosome may be a form of 

 nucleolus; (4) it becomes indistinguishable in the later stages of spermatogenesis; (5) no 

 final conclusion is reached as to whether the heterochromosome is a sex chromosome. — 

 Helen Bergfried. 



531. HiLSON, G. R. Cambodia cotton (Gossypium hirsutum). Its deterioration and im- 

 provement. Agric. Jour. India 16: 235-243. 1921. — Deterioration in India of this type of 

 cotton, originally introduced from America, is attributed to absence of selection and possible 

 crossing with other varieties. A method for improvement by selection is outlined. — T. H. 

 Kearney. 



532. Huxley, Julian S. The inheritance of acquired characters. I. Sci. Prog. IS: 

 640-641. 1921. — A letter written to the editor of "Science Progress," in which the author 

 objects to certain statements made by MacBride in his article: "The inheritance of acquired 

 characters" (see Bot. Absts. 9, Entry 252). [See also Bot. Absts. 10, Entry 541.]— PT. H. 

 Taliaferro. 



533. Jennings, H. S. Life and death, heredity and evolution in unicellular organisms. 

 U X i^l cm., 233 p., 63 fig. R. G. Badger: Boston, 1920.— The author presents for students of 

 genetics a review of their field as applied to the unicellular organisms, especially the protozoa. 

 The volume comprises the lectures delivered by the author under the Richard B. Westbrook 

 Free Lectureship Foundation at the Wagner Free Institute in Philadelphia. Chapter I forms 

 an introduction to the general subject and is a general survey of the life histories found in 

 the protozoa with especial reference to such questions as potential immortality, reproduction, 

 mating, and rejuvenescence. It is followed in Chapter II by a short summary of some of the 

 observed facts of inheritance in the protozoa. Attention is directed chiefly toward the general 

 method of inheritance of diversities, the non-inheritance of acquired characters, and the general 

 results of the "pure line" work on protozoa. Chapter III gives a brief review of the recent 

 work which has been carried out in the author's laboratory and which indicates that a race 

 descended from a single parent can be separated into hereditably diverse races by selection. 

 After considering the effectiveness of selection the author reviews in Chapter IV the question 

 of experimental modification of hereditary characteristics (inheritance of environmental 

 effects). Chapters V, VI, and VII give a comprehensive exposition of the general subject of 

 sex and the results of mating in the protozoa. These subjects are taken up from a cytological 

 as well as experimental standpoint and are considered in relation to such questions as re- 

 juvenescence, biparental inheritance and production of variations, and their relation to evolu- 

 tion. In the final chapter a comparison is made between the phenomena observed in the study 

 of genetics in the protozoa and in higher organisms; this chapter also contains a r^sum^ of the 

 general subject. Of particular interest is the reiteration of the author's view that there is 

 no essential disagreement between his work on the effectiveness of selection in the protozoa 

 and the study of mutations and modifying factors in Drosophila which has been carried out 

 by Professor Morgan and his collaborators. — W. H. Taliaferro. 



