ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 489 



A. W. Borthwick * has found a new disease of Picea. A fungus, 

 Cucurbitaria Picea sp.n., attacks the buds and hinders their growth. The 

 lower branches suffer most from the fungus. 



E. S. Salmon f writes on the Sclerotinia disease of the gooseberry 

 called " die-back " in Kent. The disease may attack leaf, berry, branches, 

 or stem. In the latter case the part of the stem first injured is on the 

 ground level or a little above it, the stem is finally ringed by the mycelium 

 of the fungus, and all growth stops. Salmon describes the conidial form 

 of the fungus, a species of Botrytis which appears constantly on the 

 diseased areas, and also the resting form, a sclerotium which enables the 

 fungus to persist through severe winter weather. Prompt removal and 

 burning of all diseased branches or bushes is urgently recommended and 

 heavy spraying with a solution of copper sulphate. 



In the same journal \ it is stated that wart disease of potatoes 

 (Chrysophlyctis endobiotica) can be checked by greening the tubers. Two 

 reasons are given to account for this : (1) The swarm-spores avoid cells 

 containing chlorophyll, and all the cells of autumn greened potatoes are 

 rich in chlorophyll ; and (2) the sprouts from these tubers are of slow 

 growth, and have developed a comparatively thick cuticle and epidermis 

 through which swarm-spores caunot penetrate. 



An account § is also given of a disease of a fig-tree somewhat 

 resembling apple canker in outward appearance. It was found to be 

 caused by a fungus Libertella ulcerata, which grows on the branches or 

 twigs and causes them to crack. In badly affected branches all parts 

 above the canker die. It is a wound parasite, and as a preventive all 

 wounds or cuts should be tarred and all diseased branches burned. 



The occurrence of Chrysophlyctis endobiotica in Ayrshire is chronicled 

 by D. A. Boyd, || who gives a detailed description of the disease which 

 appeared on potatoes grown in a nursery at Saltcoats. Agriculturists 

 are warned as to the serious nature of the disease, especially in a potato- 

 growing district, and of the necessity of securing, for seed, tubers free 

 from the fungus. The spores may lie dormant in the soil for four years 

 and then reinfect the crop. 



G. H. Pethybridge IF publishes an account of various potato diseases 

 that have come under his observation in Ireland. Chrysophlyctis 

 endobiotica is practically unknown. Black blight due to Phytophthora 

 infest ans is all too common. Various experiments were made with spray- 

 ing mixtures, the most effective being freshly made up Bordeaux mixture. 

 Stalk or Sclerotium disease {Sclerotinia sclerotioruni) is also prevalent in 

 West Ireland. It has not been ascertained how the attack occurs, as it 

 is difficult to detect in the early stages, but it is certainly promoted by 

 moist conditions due to crowding of the plants or the development of 

 weeds. It has been of advantage to dress the soil before planting with 

 Bordeaux mixture or with a heavy layer of lime. 



Much damage is also done by Cork scab {Spongospora subterranea), 



* Notes R. Bot. Gardens Edin., xx. (1909) pp. 259-61 (1 pi.). 

 t Journ. Board Agric., xvii. (1910) pp. 1-9 (8 figs.). 



t Tom. cit., pp. 46-7. § Tom. cit., pp. 47-9 (1 fig.). 



|| Glasgow Naturalist, i. (1909) pp. 62-5. 

 i Journ. Dept. Agric. Ireland, x. 2 (1910) 18 pp. (4 pis.). 



