NOTES AND ABSTEAUTS. 



533 



far the most important disease producers in deciduous trees. Those dealt 

 with include Fomes igniarius (L.) Gillet, Polyporus sulphur eus (Bull.) 

 Fr., "piped rot" caused by an unidentified fungus, Polyporus obtusus 

 Berk., Fomes nigricans Fr., Hydnum erinaceus Bull., Fomes rimosus 

 Berk., F. fraxinophilus Peck, F. fulvus Fr., Polystictus versicolor Fr., 

 Fomes Everhartii Ell. and Gall., Polyporus squamosus Huds., P. betulinus 

 (Bull.) Fr., and Fomes fomentarius (L.) Fr. 



Sap rots are described caused by Polystictus pergamenus Fr., Fomes 

 %pplanatus (Pers.) Wallr. (= Elfvingia megaloma (Lev.) Murrill), 

 Stereum frustulosum (Pers.) Fr., Daedalea quercina (L.) Pers. ; while the 

 following are briefly alluded to : Polystictus hirsutus Fr., P. sanguineus 

 (L.) Mey., P. cinnabarinus (Jacq.) Fr., Poria subacida Peck., P. vapo- 

 raria Fr., Polyporus betulinus (Bull.) Fr., P. gilvus Schwein., P. adustus 

 (Willd.) Fr., Lenzites corrugata Klotzsch, L. vialis Peck., and L. betu- 

 lina (L.) Fr. 



In each case a careful and accurate description of the diseases due to 

 the different fungi is given, with Botes on their distribution and on the 

 approved methods of dealing with them. 



The last part deals with the decay of cut timber. 



A bibliography with 114 numbers, a series of 10 plates, and an 

 excellent index complete a useful review of diseases of deciduous trees. 



F. J. C. 



Diseases of Ornamental Trees. By Haven Metcalf (U.S.A. Dept. 



Agr. Year Book, 1907, pp. 483-494).— A consideration of the diseases of 

 ornamental trees, and also the results of root suffocation, gas-poisoning, 

 &c, in town-planted trees. The possibilities of healing large wounds 

 (" Tree Surgery ") is also dealt with.— E. A. Bd. 



Dry-Rot in PotatOS. By Miss S. Longman (Jour. Linn. Soc. 

 Vol. xxxix. No. 270, pp. 120-129 ; 1909. Plate 10),— Fusarium Solani 

 causes the disease known as dry-rot. It is a true parasite attacking not 

 only the resting tuber but also the underground parts of the growing 

 potato plant. It appears on the surface of the potato either in white 

 patches (often covering wounds) or else in the form of small pustules 

 breaking through the skin at the place where it first wrinkled. The 

 earliest outward sign of the disease is the wrinkling of the skin as the 

 potato shrinks. The internal alterations of the tuber are described. 

 It has been thought that dry-rot is always preceded by wet-rot, but this 

 was found not to be the case ; dry-rot may follow wet-rot but it may also 

 affect previously healthy tubers. A description is given of the different 

 forms of spore produced by this fungus. A reduced pycindial stage was 

 observed but Massee's ascus-stage was not met with. The colour phases 

 of the mycelium and spores appear to be associated with stages in the 

 life-history of the fungus and not, as Smith and Swingle suggest, with 

 the nature of the culture-medium. Sterilization of the diseased potato- 

 tubers is not possible, since the death-temperature of the fungus is higher 

 than that of the potato. — B. B. 



Emulsions. By the Duke of Bedford, E.G., and Spencer U. Picker- 

 ing, F.R.S. (Woburn, Eighth Report, 1903, pp. 18-32).— An investigation 



