NOTES AND ABSTRACTS. 



Plum 'Pearl/ By U. P. Hedrick {USA. Exp. Stn., Geneva, 

 New York, Bull. 364). — A seedling of Burbank's, of remarkably good 

 flavour. — E. A. Bd. 



Plum *Tennant.' By U. P. Hedrick {U.S.A. Exp. Stn., Geneva, 

 New York, Bull. 364 ; plate). — One of the most attractive grown at 

 the Experimental Station at Geneva. Raised by the Rev. John 

 Tennant, Ferndale, Washington, and introduced to commerce in 

 1893.— A. Bd. 



Poisoning of Cattle in the Pasture, The. By C. K. Francis 

 {U.S.A. Exp. Stn., Oklahoma, Ann. Rep. 1912-13, pp. 20-29). — 

 Some plants are poisonous only in the spring or early summer, and 

 there is no doubt that at this season of the year they, as well as the 

 generally recognized poisonous plants, cause the death of many farm 

 animals. Investigations show hydrocyanic (prussic) acid to be 

 present, though not in the free or uncombined state, at every stage 

 of the growth of Kafir corn except the mature plant. It appears 

 that stunted plants showing the need of rain are especially dangerous. 

 All young growth of the sorghum group is liable to contain the poison. 

 The second growth of frosted plants has also been shown to be unsafe. 

 The samples containing the larger amounts of hydrocyanic acid were 

 very bitter to the taste. — A. P. 



Polyporus Berkleyi. By J. R. Weir {Phytopathology, iii. p. loi, 

 Apr. 1913 ; plate) . — This fungus attacks roots of Larix occidentalis which 

 have been damaged by some other agent previously. — F. J. C. 



Poplars, The Black. By Aug. Henry {Gard. Chron. July 4 and 

 25, 1914, pp. 1-2, 46-47, 66-67 '> 9 %s.). — Deals with the sports 

 and hybrids of the Black Poplars of Europe and America. The 

 European P. nigra differs from the American P. deltoidea in absence 

 of cilia on margin and glands on base of leaves. Both species have 

 varieties pubescent and glabrous. P. nigra var. typica is glabrous ; 

 rarely seen in this country ; native of S. and S.E. Europe. 



P. nigra var. betulifolia, with pubescent twigs, is wild in both sexes 

 in England and France. 



P. nigra var. italica is the Lombardy Poplar, a sport of P. nigra 

 var. typica, widely propagated and planted, and a staminate form. 

 Female Lombardy Poplars are hybrids, the pollen parent being this 

 tree. P. plantierensis is the fastigiate form of P. nigra var. betulifolia. 



P. deltoidea Marshall is retained as the name of the American 

 species. Var. monilijera is only represented in England by a tree 

 in Cambridge Botanic Gardens. Var. occidentalis is a xerophytic 

 form, but it and var. missouriensis have not been introduced to 

 Europe. 



P. angulata, the Carolina Poplar, cultivated in France and England 

 since 1730, differs only in the scales of the flowers, and may be a 



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