NOTES AND ABSTRACTS, 
569 
Details of morphology are given. Attempts to find an immune variety have 
been unsuccessful, but the taller of the early varieties of peas show considerably 
less disease than the later vanet.es. So far no cure is known, but attention to 
rotation, early sowing, adequate drainage, sufficiency of lime in the soil and 
burning of diseased haulm are recommended. The disease is a serious one, and 
appears to be on the increase. — /. E. W. E. H. 
Plums, Cherries, and Apples, Report on Tests of Self-sterilitv of. By I. Sutton 
{Jour. Genetics, vol. vii. pp. 281-300, Aug. 1918 ; plate). — Trials carried out by 
various observers at the John Innes Institution indicate that of Plums — ' Coe's 
Golden Drop,' ' Coe's Violet,' ' Crimson Drop,' ' Jefferson,' ' Bryanston Gage,' 
' McLaughlin's Gage,' ' Early Green Gage,' ' Old Green Gage,' ' Reine Claude 
d'Althan,' ' Pond's Seedling,' ' Wyedale,' ' Frogmore Orleans,' ' Late Orleans,' 
' Prune d'Agen,' ' Primate,' and ' Frogmore Damson ' are self-sterile ; ' Rivers' 
Early Prolific,' ' Early Favourite,' ' Cox's Emperor,' ' Early Orleans,' and ' Far- 
leigh Damson ' are partly self -sterile ; ' Denniston Superb,' ' Early Transparent,' 
' Reine Claude Violette,' ' Golden Transparent,' ' Reine Claude Bavay,' ' Oullin's 
Golden Gage,' ' Belle de Louvain,' ' Monarch,' ' Prince Engelbert,' ' Prune 
Geante,' ' Gisborne,' ' Victoria,' ' Pershore,' ' Yellow Magnum Bonum,' ' Early 
Mirabelle,' ' Kyrobalan Red,' and ' Belgian Purple,' are self-fertile. Self- fertile 
Cherries include ' Amber Heart,' ' Black Eagle,' ' Black Heart,' ' Black Tartarian,' 
' Biggareau de Schreken,' ' Noir du Guben,' ' Napoleon,' ' Jaboulay,' ' Frogmore 
Early,' ' Early Rivers,' ' Elton,' ' Governor Wood, ' Guigne d'Annonay,' ' Kentish 
Red,' ' Toussaint,' ' Waterloo,' ' White Heart ' ; ' May Duke ' and ' Archduke ' 
are partly self- fertile ; ' Flemish Red,' ' Late Duke,' and ' Morello ' are self-fertile. 
Of apples at the Institution. ' Beauty of Bath,' ' Cox's Orange Pippin,' ' Gas- 
coyne's Scarlet,' ' Lane's Prince Albert,' ' Norfolk Beauty,' ' Northern Greening ' 
appear self -sterile ; ' Worcester Pearmain,' ' Bramley's Seedling,' ' Lord Hindlip,' 
' Lady Sudeley,' ' Old English Broadleaf,' ' Doucin,' ' Improved Doucin,' Pyrus 
prunifolia, P. baccata, ' Golden Russet,' partly self-fertile ; and ' Antonowka,' 
' Annie Elizabeth,' ' Baldwin,' ' Celline Pippin,' ' Coronation,' ' Duchess of 
Oldenburgh,' ' Golden Spire,' ' King of the Pippins,' ' Lord Derby,' ' Red Winter 
Reinette,' ' Ribston Pippin,' ' Stirling Castle,' ' Sturmer Pippin,' ' Washington,' 
' French Paradise,' and ' Crimson Bramley,' self -fertile. — F. J. C. 
Plums, Winter Aspect of Buds. By E. A. Bunyard (Gard. Chron. Jan. 19, 
m 1918, p. 23, with fig.). — Calls attention to a useful method of recognizing certain 
varieties when leafless. — E. A. Bd. 
Potato, A New Strain of Rhizoctonia Solani on. By J. Rosenbaum and M. 
Shapovalov (Jour. Agr. Res. ix. pp. 413-420 ; June 1917 ; plates. — Two 
" strains " of Rhizoctonia Solani have been isolated rom the Potato, the new one 
discussed by the authors producing more pronounced lesions than the better- 
known one, both upon injured stems and tubers, and may, furthermore, be 
distinguished by its reaction growth, and the character of the sclerotia on 
d fferent med a, and by the measurements of its cells. — F. J. C. 
Potato, " Blackleg "of the. By S. G. Paine (Journ. Agr. Sci., vol. viii. part 4, 
Dec. 191 7, pp. 480-494). — The two recognized bactenal diseases of the potato 
in this country are " Blackleg " and " Brown Rot." At present they cause 
a loss of not more than 5 per cent, of the Potato crop of Great Britain, but there 
are signs that they are on the increase, and it is possible that they may become 
as serious pests with us as in Canada and Gahcia The author has made a 
thorough investigation of the organism which causes " Blackleg." This disease 
usual y appears in June. The symptoms are wuted and yeiiow leaves, which 
later turn almost black. The stem at the ground ievei shows a blackened area, 
and if gently puJled leaves the soil with hardly any resistance. There is an almost 
entire absence of development of the tubers unless infection has taken place 
late in summer. In that case the tubers are infected, the vascular ring being 
seen to be stained brown. The propagation of the disease is due as a rule to 
the planting of diseased sets, and this accounts for the fact that the disease 
makes its appearance in isolated individuals and is but rarely found to be 
affecting even small patches. It is thought, however, that the disease may be 
sometimes introduced from the soil into the plant by biting insects. 
The author shows that the organism which produces " Blackleg " of the 
potato is Bacterium atrosepticus (van Hall), and that it is identical with the 
organism which produces the disease in Ireland, and has been described by Pethy- 
bridge and Murphy under the name of B. melanogenes. 
As regards control, the planting of healthy seed tubers is obviously of great 
importance. It has also been noticed (in one instance only, however) that a 
