332 EXPERIMENT STATION RECORD. [Vol. 38 



one of splitting into tliree, and one of splitting into four types. In tlio inter- 

 crosses and back crosses no new types appear except a dwarf form referred 

 to (E. gracilis. Evidence is summarized which is considered to indicate that 

 the gametes in CE. hybrida nutans and CE. hybrida pycnocarpa are uniform. 



Inheritance of a mosaic pericarp pattern color of maize, H. K. Hayes 

 (Oenetics, 2 (1017), No. 3, pp. 261-281, fig. i).— The author describes experi- 

 ments carried out with a mosai-c pericarp pattern color in maize, employing the 

 progeny of an ear found in the course of work done with East as previously 

 noted (E. S. R., 25, p. 736), which had on one side seeds with a red pericarp 

 and on the other seeds which were white or had but a narrow red stripe. 



The first two years of the experiment showed all degrees of variation from 

 dark, heavily striped ears to ears with colorless pericarp. Later selection ex- 

 periments gave results showing the usual type of Mendelian inheritance, along 

 with some which are not easily explainable by the hypothesis of the absolute 

 purity of fundamental inheritance factors. 



Self-fertilization and selection isolated several types which bred relatively 

 true. The self-red, pattern, and colorless selections appear to be homozygous 

 for these characters, the variegated selection proving to be homozygous for the 

 mosaic character and giving ears ranging from heavy striatiou of nearly all 

 seeds to striation of only a few seeds. 



The relation of the various pericarp characters was studied, and it is sug- 

 gested that certain combinations produce germinal instability. The conclusion 

 is reached that the factors for self-red, variegated, pattern, and colorless peri- 

 carp form a series of multiple allelomorphs. 



The hybrid origin of alfalfa, L. Tkabut (Compt. Bend. Acad. Sci. [Paris], 

 164 {1917), No. 16, pp. 607-609). — The author offers what is held to be sufficient 

 evidence to show that Medicago sativa has arisen by hybridization from the 

 two primitive species AI. falcata and M. geUUa, the last named being synony- 

 mous with M. cocrulea, M. contorta, and M. tunetana. 



Origin, introduction, and primitive culture of the potato, W. P. Wight 

 {Proc. Potato Assoc. Amer., 3 (1916), pp. 35-^9) .—The author gives the results 

 of a study of early and recent accounts of the cultivated potato and of his per- 

 sonal search, chiefly in South America, for the original wild form of SoJanum 

 tuberosum. He also gives considerable information of a related but somewhat 

 miscellaneous character regarding the potato plant. 



It is stated that many of the mid species so resemble the cultivated forms 

 (so far as superficial foliage characters are concerned) that persons very 

 familiar with the latter have often been deceived. In every case, however, which 

 the author has fully investigated the plant has proved to be some other species, 

 and after a century and a half of intermittent collecting there is nowhere 

 known to be evidence showing conclusively that the species is now growing 

 indigenously anywhere in its original condition. 



It is stated that throughout a large portion of these potato-growing regions 

 the differences in soil and climate conditions are very great. The number of 

 potato varieties to be found is large and constantly increasing, some appearing 

 to be very persistent. 



Forest botany [India], R. S. Hole (Ann. Rpt. Bd. Sci. Advice India, 1915-16, 

 pp. 100-102). — A brief account is given of studies or observations on the 

 ecology of sal (Shorea robusta) ; remedies for defective reproduction by sal; 

 root disease (Polyporus shorece) of sal trees; the ecology of teak; Trametes 

 pint as a cause of disease induced by lopping Pinus excelsa; and on the forest 

 floras of the central provinces. A list of recent publications is included. 



