FIELD CROPS. 133 



planting:, it was quite clear that the thistles stimulated the growth of oats, 

 barle.v, and wheat. 



Observations were made on corn grown under a ])oplar and a hlack locust tree 

 and also about the stump of an oak tree, the tree having been removed about 

 the time the coi'n was planted. The corn grown about the oak tree stump was 

 very poor, while that under the black locust was almost equal to corn grown 

 in the garden where there was no opportunity for shade. 



The fungus symbiosis of orchids, H. Burgeff {Naturw. Wchnschr., 25 

 (1910), Xo. il, pp. 12D-13.'i, figs. 5). — A summary is given of the present informa- 

 tion relating to the symbiosis existing between certain fungi and orchids, 

 together with a description of the author's attempts to germinate orchid seeds 

 with and without cultures of fungi. 



The evolution of new form.s in Viola through hybridism, E. Brainerd 

 {Amcr. Xat.. -'i-', (1010), Xo. 520, pp. 229-236).— The author, who has been study- 

 ing the species of North American violets for a number of years, has found great 

 variation in them and attributes much of the polymorphism to hybrids occurring 

 between species in the same group. An account is given of a hybrid between 

 F. affinis and T'. saglttata which has been carried through several generations. 

 The plants were found to conform very closely to the Mendelian ratio. 



A new form of Nigella damascena obtained through mutilation, L. Blar- 

 INGHEM (Compt. Rend. Acad. 8ci. [Paris], 150 {1910), No. 7, pp. 1,06-^08).— 

 A description is given of a form of .Y. damascena that is characterized by an 

 abnormal increase in the number of carpels which are arranged in two whorls 

 within the flow^er. This form is said to have originated in 1907 from plants 

 that had been cut douia, and to be readily propagated from seed. 



A cristate form of this plant that is said to come true from seed is also 

 noted. 



Seeds and plants imported during the period from July 1 to September 

 30, 1909. Inventory No. 20 {U. 8. Dept. Agr., Bur. Plant Indus. Bui. 176, 

 pp. 3-'i). — This is a list of the more important seeds and plants secured from 

 various parts of the world during the first quarter of the fiscal year 1910 and 

 contains .329 introductions. Only those which were deemed of especial interest 

 are included, the minor importations being recorded in the office files only. 



FIELD CROPS. 



On methods in field experiments, M. Egorov {Zliur. Opuitn. Agron. (Russ. 

 Jour. Expt. Landic). 10 {1909), No. 4, pp. 502-518). — ^After a rapid survey of 

 the literature the author observes that as yet no types as regards the size of 

 plats have been established. His own contribution to this question is based on 

 experiments at the Kharkov Experiment Station. 



A level field, apparently very imiform and 240 square sjizhens in area 

 (11,700 sq. ft.), was divided into 240 square jilats (49 sq. ft. in area) on w'hich 

 oats was raised. The yields obtained are considered both as gathered from 

 single small plats and from larger plats resulting from the combination of a 

 number of these plats. The results of these groupings are indicated in the 

 following table: 



