FIELD CROPS. 31 



have shown, as the result of long investigations, that the composition of the 

 juice of Euphorbia is sutiiciently characteristic and constant to be of value as 

 a mark of the genus. Caoutchouc is said to be present but in very small 

 quantity. Euphorbou is always found, and resins are always a prominent 

 constituent. 



Heterozygosis in evolution and in plant breeding', E. M. R4.ST and H. K. 

 Hayes (Biol. CentbL, 3S (1913), No. 1, pp. 1-Jt). — This paper gives a resume of 

 experiments on the effect of crossbreeding and inbreeding with maize and Nico- 

 tiana, the details of which have been noted elsewhere (E. S. R., 27, p. 428). 



The improvement of medicinal plants, F. A. Mellee {Lilly Sci. Bui., 1. ser., 

 1912, No. 2, pp. 25-35, pis. 3). — The author points out the desirability of apply- 

 ing the principles of plant breeding to various medicinal plants in order to ob- 

 tain better and more uniform products, and briefly describes the results of some 

 work on seed selection with burdock and digitalis. 



FIELD CROPS. 



Plowing and cultivating soils in California, C. B. Lipman (California Sta. 

 Circ. 98, pp. 4)- — This circular offers suggestions in regard to handling Cali- 

 fornia soils, discussing the objects of plowing and cultivating, reasons for the 

 need of deep plowing in California, and the depth and time of plowing and 

 cultivating. 



[Report of the] division of agronomy, C. B. Williams (North Carolina 

 Hta. Rpt. 1912, pp. 16-20). — This reports experiments on the removal of corn 

 suckers (see p. 35), variety tests with cotton, wheat, oats, cowpeas and soy 

 beans, fertilizer experiments with phosphate slag, phosphate rock, Peruvian 

 guano, miscellaneous nitrogenous fertilizer tests with corn and cotton, experi- 

 ments in planting various parts of the ear, and plant breeding work with cotton 

 and wheat. 



It is mentioned that the dry weather and severe winter reduced the oat 

 yields, which for the 5 best varieties ranged from 28.7 to 32.2 bu. per acre. 

 The time of maturity ranged from 205 to 222 days. It is noted that in the 

 cotton test Russell Big Boll seemed to be better suited to a rich soil than a 

 poor one. 



Second annual report of the Miami County experiment farm, C. McIntire 

 (Ohio Sta. Bui. 256, pp. 235-251). — In a fertilizer test with corn previously 

 noted (E. S. R., 28, p. 40), tabulated results show gains in 1912 with 200 lbs. 

 acid phosphate of $4.31; with 250 lbs. phosphate and potash, .$5.57; with 300 

 lbs. complete fertilizer, $2.43 ; and with 300 lbs. complete fertilizer plus 2,000 

 lbs. powdered limestone, $2.82. In variety tests the yields per acre with soy 

 beans ranged from 20.41 bu. with Medium Green to 25.75 bu. with E^ony ; with 

 corn from 45.85 to 85.14 bu., both with Darke County Mammoth ; with oats 

 from 71.39 bu. with Wideawake to 78.59 bu. with Swedish Select; and with 

 wheat from 16.67 bu. with Kharkov to 20.67 bu. with Turkey Red. 



Data obtained at the main station along these lines are also summarized for 

 comparison. 



The work of the Belle Fourche experiment farm in 1912, B. Aune (U. S. 

 Dcpt. Agr., Bur. Plant Indus. Circ. 119, pp. 15-22, figs. 5). — This paper outlines 

 the work in progress in cooperation with several offices of the Bureau of Plant 

 Industry and Forest Service and gives some tabulated data of 1912 crop yields 

 under irrigation and dry culture in 2, 3, 4, and 6-year rotations. 



The work of the San Antonio experiment farm in 1912, S. H. Hastings 

 (U. S. Dept. Agr., Bur. Plant Indus. Circ. 120, pp. 7-13, figs. 4). — This work 

 supplements Circular 34 (E. S. R., 21, p. 535), and gives tabulated results of 



