336 EXPEKIMENT STATION RECORD. 



H. japonicus. Tbe more or less advanced age of the ovule at tke ruonient of 

 pollination affects the route by which the pollen tube penetrates to the uucellus, 

 the ovule in younger flowers being less curved than in older, yet nevertheless 

 ripe for fertilization. In younger flowers the pollen tube must pass a longer 

 way through the integuments. In certain cases, in older flowers of H. japonicus, 

 the pollen tube passes directly by the conducting tissue to the nucellus without 

 touching the Integuments. 



" The number of chromosomes in the somatic cells is 20 and 16 in H. lupulus 

 and H. japonicus, resijectively ; in the X -generation respectively 10 and 8. In 

 the tetrad formation two longitudinal divisions of the chomosomes are observed, 

 but no transverse division. 



" In abnormal, monoecious hops plants of H. lupulus it has been found that 

 the reduction division proceeds in the pollen mother-cells; but in the observed 

 cases the gonotokonts then became starved, the tapetum being already degen- 

 erated. In an abnormal, gynomon)hous male plant of //. lupulus no gonotokonts 

 developed at all, but the microsporangia were filled with sterile tissue. 



"It proved po.ssible to produce the hybrid //. lupulusXH. japonicus, but only 

 as an imperfectly formed embryo. The pollen tube of H. japonicus grew down 

 into the ovary of H. lupulus in the same way as the pollen tube of H. lupulus 

 itself, and the bastard embrj'o and bastard endosperm or only one of them 

 developed. Humulus did not develop seed without fertilization in the experi- 

 ments which were made." 



Spraying- and dusting- white potatoes, T. J. Headlee {New Jersey Stas. Circ. 

 42, pp. 3-8). — This circular gives results of testing the cost and efficiency 

 of Bordeaux mixture as a spray or as a dust, in part previously noted (E. S. R., 

 32, p. 547.) 



Data obtained from tests in various parts of the State show that the average 

 cost of four treatments of home-mixed Bordeaux and arsenate of lead was 

 $5.24 per acre, as compared with $8.46 as the average cost of the dust treat- 

 ment. The former was more effective in increasing the yield. A comparison 

 of the home-mixed and the commercial-mixed Bordeaux shows the former to 

 be less expensive and more effective. 



Potato spraying experiments at Rusli in 1914', F. C. Stewart (New York 

 State Hta. Bui. Jf05 {1915), pp. 335-339) .—T\ii& bulletin gives results of a repe- 

 tition of experiments made in 1913 (E. S. R., 31, p. 137). Owing to favorable 

 weather in 1914 potato foliage was remarkably free from diseases and injuries. 

 The average increase in yield as a result of spraying in unsprayed fields was 

 8 per cent. 



Mulched potatoes for seed purposes in eastera Nebraska, R. F. Howard 

 {Nebraska Sta. Bui. 1^6, popular ed. {1915). pp. 3-6). — A popular edition of the 

 bulletin already noted (E. S. R., 32, p. 631). 



Potato seed certification in Wisconsin, J. G. Milward {Wisconsin Sta. Bui. 

 252 {1915), pp. 11, figs. 2). — This discusses the community plan of potato grow- 

 ing, standai'ds for certificates based on varietal purity and freedom from dis- 

 ease, and methods of inspection in the field and bin. The form of certificate 

 and a list of growers of certified seed potatoes are also given. 



Results of four years' experiments with sugar cane, A. H. Rosenfeld {Rev. 

 Indus, y Ayr. Tucumdn, 5 {1915). No. 8. pp. 323-361). — This summarizes the 

 results obtained with various fertilizing materials, applied in different amounts 

 and in different combinations, as shown in the analyses of the cane juices. 



Local fertilizer experiments with sweet potatoes, J. F. Duggar and J. T. 

 Williamson {Alabama Col. Sta. Bui. 184 {1915), pp. 19-34).— This bulletin 

 describes and gives results of fertilizer experiments made by farmers in several 

 counties of the State during 1911, 1912, 1913, and 1914. 



