648 EXPERIMENT STATION RECORD. 



Carnations affected with bud rot are invariably infested with a fungus 

 associated with a particular species of mite. The same fungus and mite are 

 frequently found similarly associated on June grass {Pna pratensis). The 

 relation of the mite to the carnation disease is not entirely clear, but it prob- 

 ably acts as a carrier of the fungus. The relation of the mite to the silver top 

 of grass has not been investigated. 



The fungus on the carnation has hitherto been given a different name from 

 that on the grass, but as it was first described from the grass, the name should 

 be S. poce The mite, previously described as Pcclwiiloides dianthophilus (E. S. 

 R., 19, p. SCO), has been positively identified as Pediculopsis gramimnn. 



The authors of the present bulletin do not agree with Heald that the bud rot 

 is necessarily a disease of neglected houses, as it has proved troublesome in a 

 number of greenhouses on Long Island that are exceptionally well managed. 



The smuts of cereals, their distribution and control, R. Falck {Jour. 

 Landw., 56 (1908), No. 2, pp. 173-182. pi. 1). — This is a lecture presented 

 before the Agricultural Society of Breslau, giving a summary of information 

 regarding cereal smuts, their distribution, and means for control. 



Rust in wheat, R. H, Biffen (Jour. Bd. Agr. [London^, 15 {1908), No. 4, 

 pp. 2-'f 1-253). — After a general account of the life histories, destructiveness, and 

 other characteristics of rusts, the author describes his breeding experiments 

 with various wheats in seeking forms immune to rust, particularly to the 

 yellow rust {Puccinia gJumarum), a preliminary account of which has already 

 been noted (E. S. R., 19, p. 44). 



After finding a' number of varieties of wheat that were practically immune 

 to the yellow rust, hybridizing experiments were carried on between a variety 

 of Club, an immune variety, and Michigan Bronze, a very susceptible variety. 

 The ci'oss-bred plants proved very susceptible to the disease, but a fair crop 

 of grain was produced. A study of the material in subsequent generations 

 showed that the head characters and immunity or susceptibility are unit 

 characters that seem to be transmitted, and four fixed types have been secured, 

 namely, immune Club, susceptible Club, an immune loose-headed variety similar 

 to jNIichigan Bronze, and a susceptible variety of the same. Two of these 

 varieties closely resemble the parents and two show fresh combinations of the 

 characters present in the two parent plants. Further trials are being conducted 

 with these varieties in order to demonstrate that the new character combina- 

 tions are perfectly fixed. The immune varieties of wheat which have been 

 raised in the course of these preliminary experiments have no particular value 

 beyond their immunity. 



During the process of the investigation an opportunity was oft'ered to estimate 

 the extent of damage caused by rust. Numbers of each type were harvested 

 separately, and the yield of grain of the diseased plants compared with those 

 in a healthy condition was in the I'atio of 0.2 to 1. 



Bean diseases in 1908, H. Quernkr {Ztschr. Landw. Kaimncr Braunschweig, 

 77 {1908), No. 31, pp. 367, 368). — During 1908 serious losses were occasioned by 

 the occurrence of bean anthracnose {Gloeosporium lindemuthianum) dnd red 

 spiders {Tetranychus tclarius). For the prevention of the first, the author 

 recommends better drainage of the soil, with care in the selection of seed, and 

 where seed is suspected of being diseased, treating it with a solution of am- 

 moniacal copper carbonate. For the control of the red spider no definite means 

 are described. 



The more important diseases of cabbage in Holland, H. M. Quanjee 

 {Natuurk. Verhandel. Holland. Maatsch. Wctcnsch. Haarlem, 3. ser., 6 (1906), 

 No. 2, pp. l-Slf, pis. 8). — ^After describing cabbage culture in the north of Hol- 

 land, an account is given of some of the more important insect and fimgus pests 



