62 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Study of Sclerotinia.* — W. A. Matheny had remarked that the 

 fungus Sclerotinia fructigena grows always on pome fruits in Europe, 

 and that a form considered identical with it grows only on stone fruits 

 in the United States. He has therefore experimented with artificial 

 cultures on different fruits, and has decided that the European species 

 is different from the American brown-rot : the former is of slower 

 growth ; the conidial tufts differ in size, shape or colour, and the 

 conidia of the European form are larger, while asci and ascospores 

 apparently correspond in size, hut the spores of S. fructigena, the 

 European fungus, are sharply pointed at each end and are free from 

 guttulse. The American species he refers to S. cinerea. 



Study of Lembosia.f — T. Theiszen has written an account of the 

 genera Lembosia and Morenoella, members of the family Hemihysteri- 

 acea?. They grow on leaves and are found in warm climates, Ceylon, 

 Brazil, etc ' The genera have frequently been confused with Asterina 

 and Microthyrium. The characters of the different species (sixty in all) 

 are described, and their history traced. Synopses of genera and species 

 are added. 



Germination of Jlcidiospores.J — Otto Kunkel has made experi- 

 ments on the ascidiospores of Gseoma nitens taken from leaves of Rubus 

 frondosus. On germination they produced a promycelium in much the 

 same way as the ascidiospores of Endophyllum Sempervivi. The pro- 

 mycelium consists normally of five cells — a stalk cell without a nucleus, 

 and four nucleated cells. From each of the latter a sterigma is pro- 

 duced bearing a sporidium. The sporidia germinate immediately, 

 either forming a secondary sporidium or a germ-tube. The author 

 questions if the Gseoma nitens can have any connexion with Puccinia 

 Peckiana, as these facts seem to prove a short life-cyle. The only 

 other instance of ascidiospores known to function as rusts is that of 

 Endophyllum. 



Study of Perennial Rusts.§ — E. W. Olive divides rusts as annual 

 and occupying a limited area of the host tissue, or as perennial and un- 

 limited, pervading practically the whole host-plant with the possible 

 exception of the roots. Among these unlimited species are Puccinia 

 Podophylli, P. obtegens, and Uromyces Glycyrrhizse, the forms that were 

 examined. 



Olive found three states of mycelial distribution : an intermingled 

 growth of binucleate sporophyte and uninucleate gametophyte in the 

 same host, giving rise to spermogonia followed by ascidiospores and finally 

 by teleutospores in P. Podophylli, or by confluent uredo- and teleutosori 

 in P. obtegens and Uromyces Glycyrrhizse. 



There was also an unlimited growth of the perennial sporophytic 

 mycelium alone in the two latter forms, producing secondary uredo- and 

 teleutospores in confluent sori. 



* Bot. Gaz., lvi. (1913) pp. 418-32 (6 figs.). 



t Ann. Mycol., xi. (1913) pp. 425-67. 



% Bull. Torrey Bot. Club, xl. (1913) pp. 361-6 (1 fig.). 



§ Ann. Mycol., xi. (1913) pp. 297-311 (1 pi.). 



