454 EXPERIMEN^T STATION RECORD. [Vol. 36 



and behavior of a large witches' broom of Larix decidua studied in Switzer- 

 land, the author states that his observations agreed with those of von Tubeuf 

 (E. S. R., 24, p. 453), inasmuch as the characters of witches' broom may appear 

 to be hereditary. He states that they are transmitted not only through the 

 seeds, but also by means of grafts on normal trees. 



Peridermium harknessii and Cronartium quercuTim., E. P. Meinecke 

 {Phytopathology, 6 {1916), No. S, pp. 225-240, figs. 2).— In continuation of a 

 preliminary note (E. S. R., 34, p. 849), the author gives an account of in- 

 vestigations on the heteroecious stages of these species. 



It is stated that, while not definitely proved, it is highly probable that P. 

 harknessii is identical with P. cerebrum, and that in California P. harknessii 

 and C. quercuum are to a high degree independent of each other. The heteroe- 

 cism of P. harknessii on Pinus radiata is considered facultative, and it is be- 

 lieved highly probable that the same facultative heteroecism occurs in P. con- 

 torta and also in other hosts of Peridermium harknessii. C. quercuum winters 

 over on Quercus agrifolia, new urediniospores forming in the spring around 

 old, dead sori on old living leaves from which young leaves are infected. The 

 heteroecism of the Cronartium is also considered facultative. 



Pinus resinosa, a new host for Peridermium acicolum., R. G. Pierce 

 {Phytopathology, 6 {1916), No. 3, pp. 302, SOS). — The author reports this rust 

 as occurring on P. resinosa. 



WMte pine blister rust (Peridermium strobi) {Ann. Rpt. Ontario Agr. Col. 

 and Expt. Farm, 4I {1915), pp. 18-20). — A summary is given of the results of 

 inspection of white-pine plantations and cultivated currants, from which it ap- 

 pears that the white-pine blister rust is quite widespread in Ontario and is 

 established on native white pine, wild currants, and gooseberries. 



[Disease in pine and chestnut], F. W. Rane {Ann. Rpt. State Forester 

 Mass., 12 {1915), pp. 50-52). — It is stated that the organism causing blister 

 rust on white pine has been found on currants in the Housatonic Valley region, 

 and it is feared that it may reach the pines. 



Chestnut-bark disease is now to be found wherever chestnut grows in thia 

 section, the estimated proportion of trees attacked on a property at Mount 

 Holyoke having risen from 5 per cent in September, 1912, to 90 per cent in 

 November, 1915, and 75 per cent being in a dead or dying condition. 



Spread of the chestnut blight in Pennsylvania, H. Metcaif {Phytopath- 

 ology, 6 {1916), No. 3, p. 302). — On account of the recent statements that the 

 chestnut blight in Pennsylvania is coming to a standstill, the author presents 

 a statement from the Deputy Commissioner of Forestry of Pennsylvania which 

 indicates that the disease is continuing to spread rapidly in most localities. 



Influence of Bordeaux mixture on the rates of transpiration from abscised 

 leaves and from potted plants, W. H. Martin {U. S. Dept. Agr., Jour. Agr. 

 Research, 7 {1916), No. 12, pp. 529-5^8). — The author has carried on a series of 

 experiments at the New Jersey Station to determine the influence of Bordeaux 

 mixture on the rates of transpiration of abscised leaves of several species, as 

 well as to determine the effect of this spray material upon the rates of water 

 loss from potted plants of tomato, cabbage, pepper, eggplant, and soy bean. 



The results of these experiments are held to substantiate the general principle 

 already established by Duggar and Cooley (E. S. R., 31, p. 825) that the rates 

 of transpiration from both abscised leaves and the leaves of potted plants are 

 materially increased by an application of Bordeaux mixture. A surface cover- 

 ing of dry powdered copper sulphate was less effective In accelerating rates of 

 transpiration than was a surface film of Bordeaux mixture, but was more 

 effective than a film of barium sulphate. The acceleration of transpiration 

 rates by Bordeaux mixture was more pronounced when the spray was applied 



