290 SUMMAKY OF CURRENT RESEARCHES RELATING TO 



it to be the cause of the malady. It is described as a new species, 

 G. linicolum. The authors further discovered that the mycehum 

 hibernated within the cells of the epidermis of the seed-coat, and the 

 seedlings became infected during, or subsequent to, germination. 

 Treating shghtly moistened infected seed with a mixture of finely 

 powdered copper-sulphate crystals and dry sodium carbonate suppressed 

 the disease entirely. Other cases of " yellowing " are caused by other 

 fungi. The local designation of the disease is lacking in accuracy. 



A. L. S. 

 Recent Work at the Pathological Laboratory, Kew Gardens. — 

 Among other diseases in 1918 there have been noted several as of special 

 importance (/(9wm. Board of Affric, 1919, 26, 174-8). A bad attack 

 of yellow rust of wheat {Fuccinia glumarum) occurred in the early part 

 of the year. Much of the wheat, however, outgrew the disease. Wheat 

 mildew was prevalent in certain districts in July and August. American 

 gooseberry mildew increased materially, and Gronartmm ribicola, the 

 black currant rust, was extremely abundant. Damping oflf of seedling 

 tomatoes was caused in spring by Fhytophthora cryptogea. A leaf- 

 blotch in cucumber, due to ColletotricJmm oUgcchsetum, caused a loss of 

 several thousand pounds in Hertfordshire, Sclerotium disease of onions 

 and the new onion smut caused considerable trouble throughout the 

 country. A. L. S. 



Lichens. 



Researches on. Lichens of the Family Peltigeraceae. — Fernand 

 and Madame Moreau {Ann. Sci. Nat. Bot., 1919, ser. 10, 90,20-32). 

 In this first paper the authors outline their course of study, which at 

 present they have confined to one family of lichens. They see in the 

 symbiosis and reproduction of lichens a field of study that may produce 

 much elucidation of biological problems, and may contribute a very 

 important chapter on general physiology and pathology. A. L. S. 



Brazil Parmeliae. — Bernt Lynge {Arkiv f. Bot. K. Svensk. Vet., 

 1917-18, 15, No. 1, 1-4), publishes new records of Parmelia from Matto- 

 Grosso, and two new species, Parynelia patiscetis (Sect. Amphigymnia), 

 which recalls P. cristifera Tayl. ; and P. coccinea (Sect. Hypotrachyna), 

 distinguished by a yellow medulla, scarlet spots and lines on the surface. 

 The lobes of the thallus are narrowly laciniate. A. L. S. 



American Lichens. — Lincoln W. Riddle {Bryologist, 1918, 2, 50) 

 publishes new records for several rare lichens — Dirina repanda has not 

 been collected in the States, but specimens have been received from the 

 Bahama Islands. Lecidea cinnaharina, a boreal species, has been recently 

 collected in California. Getraria Fendleri, a Mexican plant, has been 

 found as far north as the Connecticut Valley, and Physica leucomela, a 

 tropical lichen, was found growing in Vermont. A. L. S. 



Biomorphogenesis in Lichens.— F. and Madame Moreau (Bull. 

 Soc. Mycol. France, 1918, 34, 84-5) describe the term biomorphogenesis 

 as the morphogeuic action of one organism on another. Under this 



