344 EXPERIMENT STATION RECORD. 



States and also reported from Canada, Cuba, Australia, New Zealand, and 

 various parts of Europe, are given. 



A number of causes have been assigned for this disease, but the author's 

 experiments indicate that it is not primarily due to bacteria or fungi, as is often 

 claimed. Either excessive watering or a sudden check in the water supply may 

 produce the di.sease, and certain fertilizers also tend to increase it. Among the 

 fertilizers that have been found to increase the blossom-end rot are ammonium 

 sulphate, dried blood, cotton-seed meal, and stable manure. The author is of 

 the opinion that the increase in the disease from heavy applications of water 

 and fertilizers is due to the development of harmful humic and ammonium com- 

 pounds and an accompanying decrease in nitrates. 



A bibliography is appended. 



On the presence of hibernating mycelium of Macrosporlum solani in 

 tomato seed. Ivy Massee {Roy. Bot. Gard. Kew, Bui. Misc. Inform., No. 4 

 U914), pp. 145, 146, pl- !)• — This is a condensed account of the relations of 

 M. solani, causing black rot of tomato, to its host. The hyiihse are said to be 

 of both intercellular and intracellular habit, or they may form a weft of 

 mycelium surrounding the seed and held in place, despite ordinary cleaning 

 processes, by hairs of the testa. All seed from diseased fruit is to be rejected. 



Bejuvenation of fruit stock, G. Lotrionte (Staz. Sper. Agr. ItaL, 46 (1913), 

 No. 11-12, pp. 724-754). — This is a discussion of several treatments designed 

 for use with diseased or declining olive trees, grapevines, and various other 

 fruit or ornamental plants, including soil management and use of fungicides and 

 insecticides. Directions and formulas are indicated in some detail. 



Apple cracking and apple branch, blister, P. A. van dee Bijl {Agr. Jour. 

 Union So. Africa, 8 {1914), No. 1, pp. 64-69, figs. 6). — Noting the existence of 

 Coniothecium chomatosporum on diseased apples sent in for examination, the 

 author gives brief illustrated descriptions of the disease, and outlines such 

 control measures as pruning, spraying in early spring with copper sulphate 

 (1 lb. to 25 gal. water), and three later sprayings with Bordeaux mixture pre- 

 pared according to directions given in the proportion of 4 : 4 : 50. 



Studies in gummosis and frost injuries of cherry trees. — III, The wound 

 stimulus theory, P. Soraueb {Landiv. Jahrh., 46 {1914), ^0. 2, pp. 253-273, 

 pis. 2). — Reviewing results of former studies (B. S. R., 28. p. 549; 31. p. 541), 

 and also reporting upon recent investigations, the author claims to have shown 

 to be untenable the theory that wound stimuli, whether of a traumatic or 

 parasitic nature, necessarily produce gumming. An excess of certain enzyms 

 may hinder normal cell wall formation, or may remove such structures by 

 alteration or by solution under conditions of somewhat infrequent occurrence 

 but not necessarily dependent upon previous injury to the plant. 



Peach yellows and little peach, G. G. Atwood {N. Y. Dept. Agr. Bui. 61 

 {1914), pp. 1719-1742, pis. 35). — This includes statistics of diseased orchards 

 covering 12 years, also a discussion of these diseases as related to fruit, shoots, 

 and foliage, and graphic illustrations of the changes occurring during the prog- 

 ress of each disease in several different varieties. 



The causation of these diseases has not been determined. It is held that the 

 two diseases are distinct, being probably found on separate trees, that they 

 are communicable, and that they spread rapidly from centers of infection, be- 

 ing transmitted apparently through seeds, buds, and pollen, but not through 

 soil, even when young trees are planted where old ones showing the disease have 

 stood. No curative measures have been found. Plums, apricots, almonds, and 

 nectarines occasionally show symptoms of yellows milder than those noted in 

 peaches. Neglect or delay quickly causes hea\-y losses, but prompt and 



