ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 611 



and the bulbs are gradually destroyed. The disease is not epidemic and 

 does not spread over a whole field. The Fusarium forms sickle-like 

 conidia and roundish chlamydospores ; it can be easily cultivated on 

 artificial media. 



The author calls attention to other species of the genus that attack 

 the onion or allied plants. He adds notes as to the best method of 

 treating the disease. 



Other parasitic fungi affecting onion plants are described, Macro- 

 sporum paras iticum, Cladospormm alliorum sp. n., and Altemaria tenuis, 

 which attack the leaves. Others that attack stored bulbs are also 

 recorded. 



Diseases of Plants.* — Gy. Molnar has observed the hibernation of 

 the powdery-mildew of the vine, Uncinula necator, in hot houses. The 

 myceHum of the previous year still formed a grey covering to half- 

 withered peduncles, and during the forcing season resumed activity, new 

 conidiophores and conidia being produced. On the buds of the vines 

 there was often a dense mycelium, and the conidia of the previous 

 autumn were germinating. On the inner scales he noted conidia in 

 different stages of development. The writer also records his observa- 

 tion on the appearance and development of the perithecia. He recom- 

 mends the collection and destruction of all leaves, etc., after the vintage. 



W. Robinson t has published an account of a wilt disease of China 

 asters prevalent in market gardens round Manchester and known locally 

 as " black neck." The aster may become diseased at any stage ; the 

 lower part of the stem shows a distinct browning or blackening of the 

 tissues for a short distance above the ground level, the cortical tissues 

 become decayed and the whole of the plant dies down. The fungus 

 causing the disease was proved to be a species of PhytopMhora ; the 

 sporangia showed characters similar to those of P. omnivora, but after 

 the discharge of zoospores the stalk of the sporangium grows through 

 and produces a second and even a third sporangium within the first. 

 No sexual organs were observed. 



Dezso Hegyi % describes a disease of red clover in Hungary due to 

 an attack by the fungus Gheosporium caulivorum ; during flowering the 

 plants turned black and withered. Though sporadic the disease is 

 serious, and is probably disseminated along with the clover seeds. 



The author § recommends that these should be soaked before sowing 

 in a 1 p.c. solution of copper sulphate. 



The same author records a disease of cabbage lettuce due to Mars- 

 sonia panattoniana. The outer leaves are attacked and finally destroyed. 

 The disease first shows itself as elliptical patches on the principal veins. 

 Destruction of diseased plants and disinfection of the forcing frames is 

 recommended. 



* Ampelol. Int. Eok., v. (Budapest, 1914) pp. 100-1 (9 figs.). See also Bull. 

 Agric. Intell. Rome, vi. (1915) pp. 635-7. 



t Ann. Appl. Biol., ii. (1915) pp. 125-37 (2 pis.). 



% Mezo Szemle, xxxiii. (Budapest, 1915) pp. 55-58. See also Bull. Agric. 

 Intell. Rome, vi. (1915) p. 637. 



§ Kerteszet Budapest, i. (1914) pp. 97-9. See also Bull. Agric. Intell. Rome, 

 vi. 1915) p. 637. 



