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



the wild pattern involves a 2nd dominant factor. He is therefore surprised to find that he 

 obtains merely monohybrid ratios in crosses of wild with either black, or black-and-tan; 

 this he explains by selective fertilization. As to minor variations of the wild pattern, the 

 author finds that a dark under color on the belly is dominant over pure white and gives mono- 

 hybrid ratios in back-crosses and F2. — Sewall Wright. 



88. Fruwirth, C. Zu "Wicke mit linsenformigem Samen." [To "Vetches with lens- 

 shaped seeds."] Zeitschr. Pflanzenzticht. 8: 89. 1921, — Quotations are given from an original 

 article by F, A, Wiegmann, "tjber die Bastarderzeugung im Fflanzenreiche," Vieweg, 1828. — 

 Wiegmann planted vetch and lentils together and saved seeds from each separately. Seeds 

 from the vetch parent produced plants which were similar to the mother plant but bore flat, 

 compressed seeds of paler color; hence, resembling the lentil seeds. These plants appeared 

 to breed true for their hybrid characters. — C. M. Woodworth. 



89. FuNKQUisT, H. The inheritance of the muzzle color in the cattle breed of Stjernsund. 

 Hereditas 1: 343-363, 1920, — Inbreeding has been followed in this breed for 30 years and the 

 animals are therefore closely related. The muzzles are light- and dark-colored; the former 

 are termed flesh-colored and the latter black, lead, or slate-colored. Those that are spotted 

 or slightly pigmented are termed mixed. — The study is largely made from the descendants of 

 11 bulls. Tables for each of these bulls are given, showing the muzzle color of each descendant 

 and that of the dam of each descendant. Of the 11 sires used, 6 were pigmented, 3 mixed, 

 and 2 flesh-colored. The matings of these 6 pigmented sires gave the following results : When 

 mated with pigmented dams, 225 pigmented, 48 mixed, and 11 flesh-colored; when mated with 

 mixed dams, 45 pigmented, 44 mixed, and 18 flesh-colored; when mated with flesh-colored 

 dams, 79 pigmented, 64 mixed, and 46 flesh-colored. — The mating of the 3 mixed sires gave the 

 following results: When mated with pigmented dams, 51 pigmented, 13 mixed, and 6 flesh- 

 colored; when mated with mixed dams, 16 pigmented, 18 mixed, and 16 flesh-colored; when 

 mated with flesh-colored dams, 9 pigmented, 9 mixed, and 16 flesh-colored. — The matings of the 

 2 flesh-colored bulls gave the following results: When mated with pigmented dams, 18 pig- 

 mented, 16 mixed, and 11 flesh-colored; when mated with mixed dams, 3 pigmented, 4 mixed, 

 and 7 flesh-colored; when mated with flesh-colored dams, 5 pigmented, 10 mixed, and 10 

 flesh-colored. — It is believed that the following 2 hypotheses explain the inheritance of muzzle 

 color: 1. There is an inhibiting factor preventing the intensity factors from acting. The 

 flesh-colored muzzle is due to the presence of this inhibiting factor or to the absence of the 

 intensity factors. 2. There is a yellow pigment factor epistatic to the intensity factors pro- 

 ducing dark pigment. The flesh-colored muzzle is due to the presence of this yellow pigment 

 factor or to the absence of the intensity factors. — R. R. Graves. 



90. GowEN, J. W, The variation of milk secretion with age in Jersey cattle. Maine 

 Agric. Exp. Sta. Bull. 286, 49-60. 1920.— From a study of 1741 S-months milk records, it 

 was found that yield of milk changed definitely with age and that this change was logarithmic 

 and not linear. If growth of the mammary gland is a logarithmic function of age a causal 

 relation may exist between this and yield of milk, due to an increase in the number of cells 

 rather than to an increase in the ability of cells to secrete milk. — E. Roberts. 



91. GuiNiER, Ph. Variations de sexualite dioicite et dimorphisme sexuel chez le Pinus 

 montana Mill, et le P. sylvestris L. (Variations in sexuality, dioeciousness, and sexual di- 

 morphism in Pinus montana and P. sylvestris L.] Compt. Rend. Soc. Biol. 84: 94-96. 1921. — 

 Pinus montana Mill, and P. sylvestris L., normally monoecious, were found to show a tendency 

 toward dioeciousness associated Avith the development of the trees. The production of fertile 

 pistillate branches is dependent upon vigorous vegetative growth, without which only fertile 

 staminate branches are produced. Young trees tend to function as females while older trees 

 become male-functioning only, as do also trees which have been grown under unfavorable 

 conditions. — D. F. Jones. 



