204 GENETICS [BoT. Absts., Vol. IX, 



1304. Beach, S. A. Fruit breeding in the northwest and its significance in horticultural 

 development. Proc. Amer. See. Hort. Sci. 17: 13-19. 1920 [1921]. A general discussion is 

 presented. — J. P. Shelton. 



1305. Bemmelen, J. F. van. Das Farbenmuster der mimetischen Schmetterlinge. [The 

 color pattern of mimetic butterflies.] Zool. Anzeiger 52: 269-277. 1921. — The author says 

 that one should be unprejudiced by the "mimicry hypothesis." Each group of animals must 

 be considered by itself from the point of view of comparative morphology. The same evolu- 

 tionary tendencies underlie evanescence or modification of color pattern in different families 

 and this produces forms with superficial resemblances. The more usual character in a group 

 is not necessarily the more ancestral; the 2 genera of monotremes are not derived from other 

 mammals. Narrow "mimetic" wing and body occurs in several different families of butter- 

 flies, showing that hereditary fundaments for this character are present in all. "Mimicry" 

 once appearing may be of survival value, but natural selection is not a creative force. The 

 loss of tails in females of Papilio is atavistic, for ancestral Lepidoptera have no tails. Fe- 

 males are more primitive although English writers regard "mimetic" females of P. dardanus 

 as departures from the ancestral type produced by natural selection to resemble Danaids of 

 the particular region in which they occur. Sex differences are not fundamentally different 

 from other types of variation within species. — P. W. Whiting. 



1306. Breitenbecher, J. K. The genetic evidence of a multiple (triple) allelomorph 

 system in Bruchus and its relation to sex-limited inheritance. Genetics 6: 65-90. 1921. — 

 The author finds 4 types of the "four-spotted cowpea-weevil," Bruchus maculatus, Fabr., 

 distinguished in the females by the body-colors, on the elytra and elsewhere, of red, black, 

 white, and tan. In males, the color distinctions are not sufficiently marked to make the 

 separation by the eye practicable in genetic experiments. Tan, which in females is the usual 

 color of the wild beetles, is, in general, the color of all males. Sex-linked inheritance is not 

 shown; on the other hand, sex-limited inheritance is as just explained. The "mutants," 

 as the author terms all but the tan type of female, have frequently been found in cultures from 

 various parts of the U. S. A. Each type is described. Each color is determined by a gene 

 allelomorphic to each of the other color-genes, making a multiple allelomorphic group of 4. 

 This is demonstrated by 69 different matings, producing over 100,000 individuals. The order 

 of dominance is red (dominant to all), black, white, tan; order of greatest fertility and vigor, 

 black, red, tan, white; order of greatest size, black, tan, red, white. "There is a marked varia- 

 tion as regards color. . . .For the whites may approach the blacks and the reds may verge 

 on the whites as well as on the tans." — John S. Dexter. 



1307. Buchanan, J. Arthur. The Meadelianism of migraine. Med. Rec. 98:807-808. 

 1920. — Heredity is defined in the Mendelian sense as applied to a disease and it is shown that 

 migraine conforms to the definition. The material for the study was obtained at the Mayo 

 Clinic and included 127 families with a total of 808 children. When both parents are migrain- 

 ous all the children have migraine. When neither parent is migrainous but is of migrainous 

 stock or if 1 parent only is migrainous, migraine appears among the children approximately 

 in the ratio of 1:3. "There is no medication known that will alter" the course of the disease; 

 "it is a distinct part of the patient's economy." — Howard J. Banker. 



1308. BuRCH, D. S. Pure-bred sires lead rapidly to improvement in female stock. 

 Jour. Heredity 12: 45-48. Fig. 32-34. 1921.— The author describes results of the "Better 

 sires — better stock" campaign of the Department of Agriculture [U. S. A.]. There has been 

 a distinct increase in the ownership of pure-bred females among those enrolled in the cam- 

 paign. — Sewall Wright. 



1309. Burgefp, H. Sexualitat und Parasitismus bei Mucorineen. [Sexuality and par- 

 asitism in the Mucorineae.] Ber. Deutsch. Bot. Ges. 38: 318-328. 1921. — The author reviews 

 his previous work on the Mucor parasite Chaetocladium, in which he showed the gall cell to 

 be a mixture of protoplasm and nuclei of parasite and host, and in which he suggested that the 



