390 SUMMARY OF CURRENT RESEARCHES RELATING TO 



to aggregate round the nucleus, but never round the chromatophores. 

 But where the alga] cells had been boiled, no granules were formed, 

 since the oxidase ferment had been destroyed by the boiling. It had 

 previously been supposed that the tissues of algae were free from oxidase 

 owing to the presence of reducing substances. But Reed's results show 

 that oxidases are of trerieral occurrence amonu - the altra3, though the 

 ferment appears to be capable of activating the oxidation of a limited 

 number of compounds. 



Fungi. 



(By A. Lorrain Smith, F.L.S.) 



Oidium on Citrus Trees.* — The fungus in question was found on 

 a Dancy tangerine in an orange grove at Los Angeles, S. California. 

 It was then searched for and ultimately found at several other localities. 

 The leaves only are affected ; it begins on their edges when quite young 

 as isolated spots on the upper surface. The greatest number of affected 

 leaves were found on the north and west sides of the tree towards the 

 centre and near the ground. The name Oidium tingiianium has been 

 given to the new fungus, of which a full description and diagnosis haw 

 been published. Inoculation experiments had only negative results. 



Hibernation of Vine Mildew. f — The wintering of this fungus, 

 I' miii ill k necator, is still more or less unexplained, as perithecia (the 

 winter form) seem to be seldom produced. Joseph Ibos has studied the 

 subject and publishes his observations. Perithecia had been discovered 

 by Istvanffi on grapes in 1908. Various districts in Hungary were 

 visited by Ibos in 1913, and leaves were also sent to him in a diseased 

 condition from many sources. He found on minute examination that 

 perithecia were present on many of the mildew patches. The unusual 

 abundance of these was due, he considered, to the climatic conditions of 

 the season : a cool wet summer followed by a dry warm autumn. 



Study of Peziza.J — F. J. Seaver has published photographs and 

 descriptions of some of the large Pezizse, European species that grow 

 also in the United States. The species so examined and described are : 

 Pezizabadia, on the ground in deciduous woods ; P. vesiculosa, found on 

 manure piles and rich soil ; P. pustulata, on charcoal and burnt areas ; 

 and P. sylvestris, from rubbish heaps and soil in woods. The latter 

 species is almost identical with P. pustulata in colour and size, but 

 differs in spore characters. 



Australian Cordyceps.§ — C. G. Lloyd has published illustrations 

 and descriptions of all the species of this genus recorded from Australasia. 

 All the large species come from Australia, though only six altogether 

 have been found there. Probably many more will be found. These 



* Phytopath., v. (1915) pp. 193-6 (1 pi. and 1 fig.). 



t Borassati Lapok, xlvi. (Budapest, 1914) pp. 703-1, 712-13, 728-9 (8 figs.). 

 See also Bull. Agric. Intell. Rome, vi. (1915) p. 312. 

 X Mycologia, vii. (1915) pp. 90-3 (2 pis.). 

 § Synopsis of the Cordyceps of Australia. Cinn., Ohio (1915) 12 pp. (figs.). 



