342 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



mutation after cultivation. Hybrids show such vigour among seedlings 

 that they are much cultivated. Among them are : 



P. serotina <? with ascending branches and a wide head. 



P. regenerata ? , an early-leafing form. 



P. Eugenei X Henry ana, both <? . 



P. marilandica $ , not very vigorous. 



P. rohusta, perhaps the best of the hybrids, and P. Lloydii are seed- 

 lings of P. nigra var. hetulijolia. — E. A. B. 



Potato Culture. By A. Dickens {U.S.A. Exp. Sin., Kansas, 

 Btill. 194, pp. 473-491 ; 4 figs.). — ^To avoid scab, soak the seed 

 potato for two hours in 30 gallons of water to which one pint of 

 40 per cent, formalin is added ; dry, cut, and plant. Spray the plants 

 when they are six inches high with Bordeaux mixture to prevent 

 fungoid diseases, and with lead arseniate to destroy insect pests. 



S. E. W. 



Potato Scab, Experiments relating to the Control of. By 



G. E. Stone and G. H. Chapman {U.S.A. Exp. Stn., Mass., Ann. 

 Rep. 1912, p. 84, Jan. 1913). — The experiments referred to in this 

 paper deal with the scab produced by the fungus Oospora scabies. 

 Experience has shovm that the presence of carbonates in the soil will 

 increase the amount of scab very considerably, and where these are 

 present the use of formalin, &c,, for sterilizing the tubers is of little 

 avail. A series of experiments with various chemicals, including 

 sulphur, naphthalene, formalin, carbon-bisulphide, and nicine, as 

 well as with a substance called by-product A, were carried out, and 

 with those in steam-sterilized soil gave somewhat inconclusive results. 

 The experiments are to be continued. — F. J. C. 



Potato, Spraying {U.S.A. Dep. Agr., Bull. 527, 1913). — 

 Spraying the potato with Bordeaux mixture prevents loss from blight, 

 protects the plants from insects, and stimulates the growth and 

 increases the yield. — S. E. W 



Potato-Tuber Moth, The. By F. H. Chittenden, Sc.D. {U.S.A. Dep. 

 Agr., Farm. Bull. 557, Oct. 1913 ; 4 figs.). — For many years this 

 moth {Phthorimoea operculella Zell.) has been the worst potato pest 

 in Cahfornia. It has now reached Washington and Southern Texas, 

 and menaces adjacent States. It feeds also on the tomato, egg plant, 

 and tobacco ; when it occurs on tobacco it is known as the spht worm. 

 The larvse bore between the surfaces of the leaves or into the potato 

 skin, which they mine in every direction, finally devouring the exterior. 

 There are probably several generations, and certainly another can be 

 produced in store. Therefore this insect belongs to both truck 

 crop and stored product pests. 



Clean cultivation and the extermination of all solanaceous weeds, 

 crop rotation, and turning loose hogs and sheep over infested ground, 

 are among the remedies suggested ; also fumigation with hydrocyanic 

 gas and carbon bisulphide. — V. G. J. 



