No. 1, February, 1921] GENETICS 37 



number and the types of compound grains, the degree of fissuration, the regularity or irregu- 

 larity of the forms of the grains, the chara.cters of the hilum, the distinctness and size of the 

 lamellae, the polariscopic properties, the temperature or gelatinization, the aniline reactions 

 and the qualitative and quantitative reactions with the various chemical reagents, were 

 developed or manifested in degrees beyond the parental extremes. Moreover, peculiarities 

 of various kinds were observed at times in the hybrid that were not apparent in either parent." 

 — In general he concludes that "the results of the hemoglobin and starch researches are 

 mutually confirmatory in support of the existence of stereo-isomeric forms of complex 

 organic substances that are specifically modified in relation to varieties, species, subgenera, 

 and genera, and that these specificities indicate corresponding peculiarities of the protoplasm 

 in which the substances are formed." — In Chapter VI of Volume 1, the author discusses the 

 applications of the results of his researches under the following headings: specificity of 

 stereo-isomerides in relation to genera, species, etc. ; protoplasm a complex stereo-isomeric 

 system; the germ-plasm a stereochemic system; protoplasmic stereochemic system applied 

 to the explanation of the mechanism of variation, sports, fluctuations, etc. ; protoplasmic 

 stereochemic system applied to the genesis of species.— Part 2 (a separate volume), "Special, 

 general and comparative laboratory data of the properties of the starches and of the tissues 

 of parent-stocks and hybrid stocks," consists of the laboratory records prepared by two of 

 the author's assistants. Dr. Elizabeth E. Clark, and Miss Martha Bunting. — M. F. 

 Guyer. 



2.36. RosE.VBERG, O. Weitere Untersuchungen iiber die Chromosomenverhaltnisse in 

 Ctepis. [Further studies on the chromosome relations in Crepis.] Svensk. Bot. Tidskr. 

 .'4: 319-325. 5 fig. 1920. — In Crepis Rente riana there are quite normal grains with only 

 two (normally three) chromosomes to be found. This depends on abnormalities in the reduc- 

 tion division. Of Crepis Reuteriana (2x = 6) a gigas mutation with 12 somatic chromosomes 

 is found, each of the three chromosome types being represented by four chromosomes. A 

 great deal of polyploidy is now known in the genus. Crepis biennis and others have 42 

 somatic chromosomes. These species may be interpreted as 14-ploid, possessing only the same 

 3 typos of chromosomes as we find in Crepis virens, but repeated 14 times.— X. V. Ossian 

 Dahlgren. 



237. RuNNSTROM, J. Bsfruktningens och fosterutvecklingens problems. [The problems 

 of fertilization and embryology.] Vetenskap o. Bildniiig 30. 2S2 p., 109 fig. A Bonnier: 

 Stockholm, 1920. — Contains a treatise on the origin and evolution of the cell-idea. Aims to 

 give a comprehension of the physiology of cell-division and fertilization, illustrating chief 

 problems of the mechanics of evolution by some examples. Last chapter treats of endo- 

 crine secretion of sex-glands, etc. Some results are new, being taken from the author's own 

 still unfinished studies on the mechanics of evolution as exemplified in sea-urchin eggs. 

 Working with sea-w^ater free from K or Ca, may produce a symmetrical system perpendicular 

 to the normal one. Author also demonstrates some experiments to eliminate the echinid 

 rudiment which is to be found at the left side of the larva. In spite of the extirpation of 

 this rudiment, certain symmetrical changes take place in the alimentary canal. A new 

 mouth and a new oesophagus may be developed. The latter is often produced in a manner 

 different from that of the normal metamorphosis. Changes of the rectum diiTering from 

 normal development are also found. In some cases three quite atypical organs have been 

 discovered: (1) A ciliated organ, that produces an excretion, in connection with the anus. 

 (2) An outgrowth from the body, produced by cylindrical epithelium with capacity of secre- 

 tion and liable to be regenerated. (3) A pocket-like formation with ciliated cells. The 

 author considers that genes exist in sea-urchin eggs, the effects of which are normally sup- 

 pressed by the great development of the echinid rudiment. — K. V. Ossian Dahlgren. 



238. Ruzicka, Vladislav. Restitution und Vererbung. Experimenteller, kritischer 

 und synthetischer Beitrag zur Frage des Determinationsproblems. [Restitution and heredity. 

 Experimental critical and synthetic contribution to the problem of determination.] Vortr. u. 

 Aufsatze u. EntAvicklungsmech. Org. 23 : 69 p. 1919. 



