210 GENETICS [Bot. Absts. 



1478. Dorsey, M. J. Relation of weather to fruitfulness in the plum. Jour. Agric. Res. 

 17: 103-126. PI. 18-15, 1 fig. June 16, 1919. — A summary of evidence bearing on the influence 

 of weather on pollination and fertilization in the plum. Conclusions are based on studies 

 of others and on personal investigations. Observations of field conditions in Minnesota, 

 from 1912-1918 inclusive, are supplemented by greenhouse experiments and by cytological 

 studies. — Rain and low temperatures during periods of bloom are the most important factors 

 of weather. Rain prevents or delays dehiscence of anthers and interferes with activity of 

 insects. But anthers that have already opened will close under influence of rain without much 

 loss of pollen, and pollen is not seriously injured by rain as has been very generally believed. 

 The washing of pollen from stigmatic surfaces by rain is not an important factor. Prolonged 

 periods of rain reduce fruitfulness chiefly by interfering with and delaying the proper dis- 

 semination of pollen. — Periods of low temperature ranging from 40° to 51° decidedly retard 

 growth of pollen tubes and thus vitally influence fertilization. Pistils are receptive from 4 

 to 6 days, abscission of styles occurs from 8 to 12 days after flowers open, and pollen tubes 

 normally make slow growth. Conditions which retard growth of pollen tubes therefore ren- 

 der fertilization uncertain. The severe effects of frosts are only occasional in Minnesota. — 

 Wind pollination is found to be insufficient. Strong winds at critical times affect fruitfulness 

 by interfering with activities of insects. — "Each season certain sets of conditions can be 

 singled out as being largely responsible for the status of the setting of fruit," but practical 

 means of controlling rain, temperature, and wind "under orchard conditions do not appear 

 readily available." The author concludes that "since tube growth seems to be the process 

 most directly affected by low temperatures, remedial measures can most effectively be sought 

 in suitable pollinizers which show the fastest tube growth." [See Bot. Absts. 3, Entry 1529.] 

 —A. B. Stout. 



1479. Fatjre, Ch. Note sur un cas d'hermaphroditisme rudimentaire chez le coq. [Note 

 •on a case of rudimentary hermaphroditism in the cock.] Compt. Rend. Soc. Biol. France 82: 

 519-520. May 17, 1919. — Brief description of a bird regarded by the author as an instance of 

 false hermaphroditism in the domestic fowl. — H. D. Goodale. 



1480. Frets, G. P. [Rev. of: Schallmater, W. Vererbung und Auslese. Grundriss 

 der Gesellschaftsbiologie und der Lehre vom Rassedienst. (Heredity and selection, funda- 

 mentals of social biology and science of race improvement.) 3rd ed., 8vo., xvi + 536 p. Gus- 

 tav Fischer: Jena, 1918. (See Bot. Absts. 2, Entry 701.) Genetica 1: 492-495. Sept., 1919. 



1481. Goedewaagen, M. A. J. [Rev. of: Davis, B M. Some inter- and back-crosses 

 of Fi Oenothera hybrids. Genetics 2: 155-185. 1917.] Genetica 1: 466-46S. Sept., 1919. 



1482. Haecker, V. [Rev. of: (1) Trubexbach, P. Plymouths in Wort und Bild. (Ply- 

 mouth Rocks in description and illustration.) Gefliigelwelt (Chemnitz) 96 p., 50 fig. 1913. 

 (2) Idem. Weisse Wyandottes, ihre Zucht und Pflege. (White Wyandottes, their breeding 

 and care.) Ibid. 100 p., 2 pi., 107 fig. 1915.] Zeitschr. indukt. Abstamm. Vererb. 20: 160- 

 173. IS fig. Jan., 1919. 



1483. Harper, R. A. The structure of protoplasm. Amer. Jour. Bot. 6: 273-300. 1919. 

 —See Bot. Absts. 3, Entry 2133. 



• i 



1484. Ikeno, S. Idengaku de iwayuru "korosu" Gen ni tuite. [On the so-called "lethal 

 factor in genetics.] (Japanese.) Rigakukwai [Scientific World] 16: 881-886. 1919. — A popu- 

 lar paper concerning lethal and semi-lethal factors. Illustrations are given both from vege- 

 table and animal kingdoms. [See Bot. Absts 3, Entries 1934. 2133.] — S. Ikeno. 



1485. Jones, W. N. On the nature of fertilization and sex. New Phytol. 17: 167-188. 

 1918. — Interpretation of sex phenomena in both animals and plants by postulating the exist- 

 ence of two sets of sex agents: (1) those determining the sex of the individual, inherited ac- 

 cording to the ordinary Mendelian scheme (the sex chromosome or factors). These may be 



