112 PATHOLOGY [Bot. Absts. 



765. Gatjman, E. tiber die Spezialisation der Peronospora calotheca DeBary. [Speciali- 

 zation of P. calotheca.] Svensk Bot. Tidsskr. 12: 433-^45. 2 fig. 1918. — Using Peronospora 

 calotheca from various plants, the author made infection experiments and measured a large 

 number of conidia. The conclusion is reached that the Peronosporae on different species of 

 the Rubiaceae are not only biologically but also morphologically different. — Instead of using 

 the specific name Peronospora calotheca for all forms on Rubiaceae, different specific names 

 should be applied to the forms on different hosts. Four new species of Peronospora are de- 

 scribed. — J. Roseribaum. 



766. Gauman, E. Uber die Spezialisation der Peronospora auf einigen Scrophulariaceen. 

 [Specialization of Peronospora on Scrophulariaceae.] Ann. Mycolog. 16: 189-199. 6 fig. 1918. 

 — As a result of infection experiments, the author concludes that in the case of Peronospora 

 found on plants belonging to the Scrophulariaceae possibly a greater biologic specialization is 

 found than in many Uredineae. Study of the conidiophores and conidial measurements show 

 that the majority of these biologically specialized forms can also be distinguished morpholog- 

 ically. — In some cases two different morphological species occur on the same host. Perono- 

 spora on Linaria vulgaris is mentioned as an example. In this case one form occurs on the 

 reproductive and the other on the vegetative parts. — Seven new species of Peronospora are 

 described. — J. Rosenbaum. 



767. Gentner, G. Uber durch Macrosporium sarciniforme Cav. hervorgerufene Erkrank- 

 ungen der Luzerne und des Klees. [Diseases of alfalfa and clover caused by M. sarciniforme.] 

 Prakt. Blatt. Pfianzenb. u. Pflanzensch. 16: 97-105. 1918.— See Bot. Absts. 3, Entry 2651. 



768. Gough, G. C. Wart disease. Gard. Chron. Ill, 63:206. Fig. 90. 1918.— Review 

 of recent literature on potato wart "caused by Synchitrium endobioticvm." — D. Reddick. 



769. Graves, Arthur Harmount. Some diseases of trees in greater New York. My- 

 cologia 11: 111-124. PI. 10. 1919.— A bark disease of the butternut is described in which 

 limbs and whole trees are killed; Melanconium oblongum is associated with the disease. The 

 most destructive disease of sweet birch, the symptoms of which are typical lipped cankers, is 

 due to Creonectria coccinea (Pers) Seaver (Nectria coccinea Fr.). Winter injury or leaf scorch 

 of the beech, heart rots of oaks caused by 3 fungi (Globifomes graveolens (Schw) Murr., Ino- 

 notus hirsutus (Scop.) Murr., and Pyropolyporus everhartii (Ellis & Gall.) Murr.), a bark dis- 

 ease of the paper mulberry caused by Creonectria purpurea (L.) Seaver (Nectria cinnabarina 

 Fr.), injury to various trees from severe winter conditions of 1917-18, are among other dis- 

 eases discussed. — H. R. Rosen. 



770. Hill, Gerald F. History of citrus canker in the Northern Territory. Bull. North- 

 ern Territory, Australia 18. 8 p., 8 pi. 1918. — An account of the discovery of citrus canker 

 and the results of a subsequent careful examination of practically all known citrus trees in 

 the Northern Territory of Australia, to which Territory the disease is confined. The disease 

 has been found at Stapleton, Port Darwin, Darwin Botanic Gardens, Darwin Post Office, 

 Point Charles Lighthouse, Cape Dow, and at the Aboriginal Reserve at Oenpelli. The dis- 

 covery at Stapleton was made in December, 1912. Pseudomonas citri was isolated and identi- 

 fied. In the sections of the territory where the disease is found, infection is severe. — Spraying 

 with Bordeaux mixture (4: 4: 50) and with copper soda sprays was ineffectual. All citrus trees 

 in the infected areas have been burned and growing or importation for a period of five years pro- 

 hibited. Government proclamation in 1915 prohibited importation of citrus trees from any 

 part of the world. Later modification allows importation from California and Arizona, U. 

 S. A. — Most of the trees in the infested regions came from the Botanic Gardens, Darwin. 

 There is good evidence to show that the disease was introduced into Darwin Botanic Gardens 

 from China and Japan. — J . P. Benson. 



771. Hiltner, L. tiber Anquellung, Beizung und Impfung des Saatguts. [Soaking, dis- 

 infecting and inoculating seed.] Prakt. Blatt. Pfianzenb. u. Pflanzensch. 16: 105-111. 1918. 



