474 FUNGI IMPERFECT!. 



Actinonema. 



Pycnidia small and situated on a gossamer net of mycelium. 

 Conidia hyaline and divided by one or more cross-septa. 



Actinonema rosae Lib. {Asteroma radiosmn Fr.). This pro- 

 duces black radiating spots on rose-leaves, on which pycnidia 

 with bicellular conidia are developed. A premature defoliation 

 takes place, which in turn causes the upper buds to unfold in 

 autumn before their time. The mycelium is distributed both 

 inside the leaves and superficially. Timely removal of diseased 

 leaves and defoliated shoots might be recommended as remedial 

 measures. 



A. tiliae Allesch. shows itself in spotting of the leaves and 

 petioles of lime, and may bring about defoliation of the whole tree. 



A. fagicola Allesch. produces white spots with dark margins 

 on living beech leaves, and causes gradual discoloration of the 

 whole leaf. According to Allescher,^ this disease brings about 

 premature defoliation of beech. As yet it has been observed only 

 in Upper Bavaria. 



A. fraxini Allescli. On living leaves of the ash. 



A. crataegi Pers. attacks leaves of Pijrus Aria, P. torminalis, and 

 Viburnum Opvlus. 



A. podagrariae Allesch. On living leaves of Aegopodium Podagraria, 

 and Chaerophyllum hirsntvm. 



Darluca. 



Darluca genistalis (Fr.). On living leaves of Cytisus sagiltaUs. This may, 

 however, be only a parasite on Uromyces cytisi with which it is frequently 

 observed, just as Dar. filum occurs on several Uredineae. 



Diplodina. 



Similar to DipIuiJia, but having colourless conidia. 

 D. castaneae Trill, et Delac." produces canker-spots on the 

 stems of chestnut, and brings about death. 



Phragmosporae. 

 Hendersonia. 

 Pycnidia formed under the host-epidermis, which is later 

 ruptured. Conidia brown, two- or more-celled. 



1 Allesoher, Iledim'r/ia, 1894. 



'^Frillieux et Delacroix, Bull. .soc. mycol. de France, 1893. 



