No. 3, October, 1921] GENETICS 221 



that are apparently fertile, or partially so, produce fruits inferior in size to those set under 

 natural conditions. Cross-pollination experiments are necessary to determine the best pollin- 

 izers for any commercial variety. A test of 9 varieties in 16 crossesshows a wide variation in 

 results; the percentage ranging from for Grimes X Gravenstein and Wagener X Gravenstein, 

 to 35 for Spitzcnburg X Grimes, and 34.5 for Newtown X Jonathan. — In selecting a pollinizer 

 the following points require consideration: 1st, mutual affinity is necessary between varieties 

 planted together; 2nd, the 2 varieties must bloom at approximately the same time; and, 3rd, 

 the varieties should be good pollen-producers. — For existing orchards, grafting over (at 

 least 1 tree in 10) of a variety deficient in pollen production with a variety producing abun- 

 dant pollen, is suggested. One hive of bees to the acre, especially during the blooming 

 period, would unquestionably increase the normal set of fruit. [See also Bot. Absts. 6, 

 Entry 1164.]— C. S. Crandall. 



1380. Watson, J. A. S. A Mendelian experiment with Aberdeen-Angus and West High- 

 land cattle. Jour. Genetics 11: 59-67. PI. 12. 1921. — Coat, conformation, horns, and color 

 were included in the investigation. No definite information was obtained concerning coat 

 and conformation. Polled and horned characters form a simple Mendelian pair. In the 

 female, the polled condition is completely dominant while in heterozygous males the devel- 

 opment of horns is sometimes but not always completely suppressed. — Black and red are 

 allelomorphic, black being dominant. The relation of dun to black and red is not clear. 

 Different hypotheses are discussed. — E. Roberts. 



1381. Whipple, O. B. Methods in pure-line selection work with potatoes. Proc. Amer. 

 Soc. Hort. Sci. 14: 34-38. 1917 [1918]. — A general discussion is presented. — J. P. Shelton. 



1382. Wkiedt, Chr. Albinisme i hester. Borket, hvitborket og gule. [Albinism in 

 horses. Three types of dun involving the albino factor.] Tidsskr. Norske Landbr. 1918: 

 396-406. 1918. — Albino horses are not mentioned in the earlier publications on the inheri- 

 tance of coat color in horses. In the 2 Norwegian breeds of horses, the Gudbrandsdalians 

 and the Fjords, albino individuals sometimes occur. In the present publication it is demon- 

 strated that several types of dun are the heterozygotes of the albino factor. Three such types 

 of dun are recorded. In the 1st case the albino factor reduces the brown or bay color to a 

 type of dim called "borket." In this type of dun the same black markings as those of brown 

 and bay are found. The not-black color is a golden yellow, especially in the summer. The 

 second type, in Norway termed "gul" (yellow), is the heterozygote of albino and chestnut. 

 These individuals lack the black markings, but the skin is pigmented and the hairs are of the 

 same golden yellow color as in the 1st type. In the 3rd type, termed "hvitborket," the al- 

 bino factor is in combination with a dominant dilution factor which reduces brown and bay 

 to a type of dun called "blak." "Blak" is the same type of color as the one found in the Pre- 

 valsky horse. "Hvitborket" hairs have the same black points as bay, but the rest of the hair 

 has a very faded yellow, nearly white, color. — The data presented show a clear-cut segrega- 

 tion of albinos in both the "borket" and the "hvitborket" crosses. "Borket" X "borket" 

 gave 2 brown or bay, 7 "borket," and 2 albinos. Different authors are cited, their data all 

 showing the same kind of segregation. "Hvitborket" X "hvitborket" gave 6 "blak," 2 

 brown or bay, 18 "hvitborket," and 16 albinos. Brown or bay X albino gave 10 "borket." 

 "Blak" X albino gave 8 "hvitborket." The back-cross "borket" X brown or bay gave 119 

 "borket," 7 "gul" (yellow), 143 brown or bay, and 7 chestnut. The back-cross "hvitborket" 

 X "blak" gave 25 "hvitborket," 29 "blak," 1 "r0blak" (chestnut reduced by the dilution 

 factor), and 1 brown or bay. The data concerning "gul" are scarce. A single cross of albino 

 X chestnut gave "gul." "Borket" X chestnut gave 7 "borket," 4 "gul," and 1 chestnut. 

 "Gul" (yellow) X brown or bay gave 6 "borket," 2 "gul," 9 brown or bay, and 1 chestnut. 

 The mating albino X albino has in Beberbeck given albinos without exception in 200 cases. — 

 The albino color in horses behaves nearly in the same way as does albino in guinea-pigs. 

 Individuals are found which have some pigment on ears, mane, and tail. — Otto L. Mohr. 



1383. W[right], S[ewall]. [Rev. of: Castle, W. E. Genetics and eugenics. 27id 

 ed., 15.5 X 23.5 cm., 395 p., 7 pi., 155 fig. Harvard Univ. Press: Cambridge, Massachusetts, 

 1920 (see Bot. Absts. 7, Entry 1734).] Jour. Heredity 12: 71. 1921. 



