270 PATHOLOGY [Bot. Absts., Vol. V, 



peaches {Amygdalus persica) against diseases and insects. In the garden and truck work, 

 spraying against the Mosaic disease of peppers {Capsicum annuum) was undertaken. Black 

 Leaf 40 was used against the plant lice in an effort to prevent spread of the trouble. Experi- 

 ments appeared successful, but it was found hard to control the lice. This work will be con- 

 tinued. — The breeding of cotton (Gossypium hirsutum), the testing of varieties and the 

 growing of wilt resistant strains were part of the activities of the Board during 1918. — Two new 

 insects were reported in Georgia, one being a species of Margarodes and the other the Chrys- 

 anthemum Midge (Diarthronomyia hypogaea) . The latter part of the report contains a list 

 of the Georgia nurseries inspected for 1918-1919. — T. H. McHatton. 



2062. Lloyd, C. G. Mycological notes, No. 61. P. 877-993, pi. 124-139. Cincinnati, 

 Ohio, 1919.— See Bot. Absts. 5, Entry 1959. 



2033. Matz, Julius. Algunas enfermedades del follaje en las plantas. [Foliage diseases.] 

 Revist. Agric. Com. y Trab. 2: 624-625. 1919. — Reprinted from Revist. Agric. Puerto Rico. 



2064. McKay, M. B. Verticillium wilt of potatoes in Oregon. Potato Mag. 2 6 : 10-11, 38, 

 42. 5 fig. 1919. — V. albuatrum may be present in apparently healthy tubers and absent in 

 tubers with discolored strands. It may survive a winter in either end of a tuber from a dis- 

 eased hill, or in trash from diseased plants in the soil. The fungus first attacks the small 

 roots. It spreads through the soil along the row. Infection in 90 per cent of the hills reduced 

 the yield by 32.5 per cent. — Donald Folsom. 



2065. McRae, W. Administration report of the Government Mycologist for the year 1917- 

 18. Rept. Dept, Agric. Madras 1917-18: 77-80. 1918.— A progress report of the work being 

 done on miscellaneous diseases is given. — J. I. Lauritzen. 



2066. Melhus, I. E., and L. W. Durrell. Cereal rusts of small grains. Iowa Agric. 

 Exp. Sta. Circ. 62. 15 p., 11 fig. 1919. — The five different rusts commonly attacking the small 

 grains are described in a popular manner. The time of appearance of stem rust (Puccinia 

 graminis) in the spring and its spread from the common barberry (Berberis vulgaris) is shown 

 in tabular and graphic form. During the past two years (1917 and 1918) a great many bar- 

 berry bushes have been found in the state growing as hedges in the country and town or as 

 clump plantings on public and private grounds in the cities. Previous to 1917, all of the nurs- 

 eries in the state carried extensive plantings for distribution. In some cases these plant- 

 ings covered five acres. In addition to being domesticated, this shrub is at present tending 

 to run wild in some localities, 20 such places having been found. Data at hand show that in 

 1917 before the barberry eradication movement was begun, there were in Iowa at least a 

 million bushes. Their distribution was general over the state, and they were found in every 

 county, although the largest numbers were found in the larger cities. The relation of crown 

 rust to the various species of buckthorn (Rhamnus) in the state is explained. There are three 

 species of buckthorn in Iowa. Two of them have been introduced from Europe and are sold 

 by nurserymen for ornamental and hedge purposes. These are Rhamnus cathartica and R. 

 frangula. The latter species is very resistant to the alternate stage of crown rust. — I. E. 

 Melhus. 



2007. Melhus, I. E., and L. W. Durrell. Studies on the crown rust of oats. IowaAgric. 

 Exp. Sta. Res. Bull. 49: 115-144. 6 fig. 1919. — -A progress report dealing largely with factors 

 influencing the growth and reaction of crown rust on oats and different species of Rhamnus. 

 The minimum, optimum and maximum temperatures for urediniospore germination are given. 

 The per cent of germination of urediniospores produced in the greenhouse is variable. Ure- 

 diniospores must be in direct contact with water in order to germinate. Vaseline and paraf- 

 fine oil in contact with water acted as stimulants. The special form of crown rust on oats 

 uses Rhamnus cathartica and R. lanceolala as alternate hosts. R. frangula, R. caroliniana 

 and R. alnifolia, according to the data presented, do not harbor the aecial stage of crown rust 

 of oats. — I. E. Melhus. 



