1916] AGRICULTURAL BOTANY. 227 



Peat organisms that slowly liquefy agar, T. F. Manns (Abs. in Science, n. 

 ser., 43 {1916), No. II04, p. 289).— While making a study of the flora of raw 

 peat and muck, the author observed that certain colonies of bacteria were able 

 to break down the agar and cause a deep pitting in the medium. The or'ganism 

 appears to be a micrococcus and to be most abundant in peat that is composted 

 with ground calcium phosphate and calcium carbonate. 



The transmission by maize seeds of the effects of detasseling, E. Heckel 

 (Compt. Rend. Acad. Sci. [Paris], 161 {1915), No. 12, pp. 33S-340 ; Prog. Agr. 

 et Vit. {Ed. VEst-Centre), 36 {1915), No. 50, pp. 570-572).— Following up his 

 previous work (E. S. R., 33, p. 426), the author took four strains of Giant 

 Serbian maize bred during the previous four years, the stalks being detasseled 

 each year after the accomplishment of fertilization, and after detasseling the 

 stalks August 20, 1915, tested them at intervals for sugar, as possibly showing 

 the cumulative effects of traumatism on the sugar content. 



Each of the four series tested, while showing an increase over its control in 

 saccharose and a decrease in glucose, showed an increase in the total of both, 

 the greatest percentage of total increase of these sugars being obtained from 

 the strains previously showing only moderate sweetness, and the maximum 

 increase being attained in 24 days after detasseling. Starch was present in 

 all the stalks that had been detasseled. 



Experiments in recombining endosperm colors in com, R. A. Harpek {Abs. 

 in Science, n. ser., 43 {1916), No. IIO4, p. 290). — Attention is called to the fact 

 that well-established black races of corn, when crossed with white races, give, 

 both in the Fi and Fa generations, a series of colors including dark purples, 

 reds, blues, grays, etc. The author has undertaken a series of recombination 

 tests, but no immediate and uniform return to the ancestral black has been 

 obtained as yet. 



The chlorophyll factors in Lychnis dioica, G. H. Shull {Abs. in Science, 

 n. ser., 43 {1916), No. IIO4, p. 290). — According to the author, three Mendelian 

 factors are responsible for the chlorophyll of the normal dark green biotypes of 

 L. dioica. One of these differentiates all green strains from albinos and is 

 capable only of ephemeral existence. A second, acting in conjunction with the 

 first, produces a form with possibly two-thirds as much chlorophyll as the nor- 

 mal. The third factor acts in conjunction with the other two to produce the 

 full green color. 



Orthogenetic saltation in Nephrolepsis, R. C. Benedict {Abs. in Science, 

 n. ser., 43 {1916), No. IIO4, p- 292). — The author describes some forms of dis- 

 continuous variation in A^^. exaltata bostoniensis. In this variety there are 

 said to be at least three distinct lines of variation, progressive dwarfing, pro- 

 gressive increase in division of leaf, and progressive increase of waviness of 

 leaf, each variation being represented by a number of forms. 



Evidences of hybridism in the genus Rubus, C. S. Hoar {Abs. in Science, 

 n. ser., 43 {1916), No. IIO4, pp. 290, 291). — The author presents morphological 

 data considered to favor strongly the occurrence of widespread hybridism in 

 the genus Rubus. There is believed to be good evidence from the standpoint 

 of extreme variability and correlated gametic sterility of widespread natural 

 hybridism in this genus. 



An interesting modification in Xanthium, C. A. Shull {Abs. in Science, 

 n. ser., 43 {1916), No. IIO4, pp. 292). — A peculiar modification of burs of Xan- 

 thium is described, in which the number of the flowers surrounded by the 

 involucre has been greatly increased. The manner in which the form 

 originated is unknown, but it is thought to be either a mutation or a reversion 

 from X. canadense. 



