636 EXPERIMENT STATION" RECORD. 



from the middle seed and the yield of seed from the tips is 105 per cent of 

 that from seed from the middle of the ear. In the case of the tips this is 5 

 times the probable error for the series, and in the case of the butts, 3J times. 

 These percentages, though small, must be considered significant in a table of 81 

 instances. ... In 4 out of the 81 cases reported we may be sure that the 

 yield has been increased by the use of tip seed, and in the other cases there is 

 no evidence that the use of top seed has decreased the yield. In four cases the 

 Increased yield from butt seed is more than four times the probable error. 



" The conclusion of the matter seems to be that the tips and butts are cer- 

 tainly not inferior for seed purposes, and there seems little justification for 

 the practice, prevalent in some sections, of discarding them for seed." 

 A bibliography of 25 titles is appended. 



Flax for seed and oil. — Harvesting and storing the crop for seed and oil 

 purposes, H. L. Bolley {North Dakota 8ta. Girc. 7 {1915), pp. ^).— Practical 

 suggestions for the harvesting and storing of flax for seed and oil purposes are 

 given. 



Flax crop conditions for 1915 {Montana Sta. Circ. 48 {1915), pp. 5-8). — 

 This circular discusses the methods of production and prices obtained for flax 

 with reference to Montana conditions. 



The potato crop in Montana, O. B. Whipple {Montana Sta. Circ. 46 {1915), 

 pp. 141-165, figs. 11). — In this circular the author discusses methods of produc- 

 tion with special reference to the improvement of the potato crop and the 

 growing of potatoes for seed purposes, and includes irrigation and marketing. 

 Descriptions are given of the most important types of potatoes. 



Potato spraying and dusting in New Jersey, TJ. S. A., A. E. Cameron 

 {Bui. Ent. Research, 6 {1915), No. 1, pp. 1-21, pis. 3, figs. 2).— A report of work 

 already noted from another source (E. S. R., 33, p. 336). 



Experiments in covering cane by plow and by spade, A. H. Rosenfeld 

 {Internat. Sugar Jour., 17 {1915), No. 200, p. 36//).— In tests conducted at the 

 TucumSn Experiment Station cane covered in planting with a small share plow 

 produced at the rate of 39,105 kg. per hectare (17.4 tons per acre) as compared 

 with 35,254 kg. for that covered with a spade. 



Possibilities of the sweet potato in Macon County, Alabama, G. W. Carveb 

 {Alabama Tuskegee Sta. Bui. 30 {1915), pp. 22, figs. S).— A revised and slightly 

 enlarged reprint of Bulletin 17 already noted (E. S. R., 22, p. 729). 



Notes on the germination of tobacco seed, II, T. H. Goodspeed {Univ. Cal. 

 Puh., Bot., 5 {1915), No. 7, pp. 233-248) .—This reports the continuation of work 

 previously noted (E. S. R., 29, p. 739), and presents further evidence regarding 

 the relation between the age of the seed of certain pure-line cultures and of the 

 seed of hybrids made between .them, and the viability of this seed. 



The data " concerning the germination of hybrid v. parental seed leave no 

 doubt that different plants of F,, F2, and Fa produce seed the germination of 

 which is significantly differentiated as to the total amount of the seed that will 

 germinate, or as to the length of time during which germination takes place, or 

 as to the period, during the extent of the test, within which the maximum 

 amount of germination occurs. Further, there is evidence that among the 

 seeds of a single F2 or F3 plant a portion have a characteristic period during 

 which they germinate, which is distinct from the period characteristic of an- 

 other group of the same seed. . . . Finally, the Fi seed from reciprocal crosses 

 has been shown to differ with reference to its germination. In this connection, 

 either the amount of total germination, or the extent of the germinating period, 

 or the days of maximum germination peculiar to one parent have been shown 

 also to be characteristic of the cross-pollinated seed which it bore." 



