474 FUNGI IMPERFKCTI. 



Actinonema. 



Pycnidia small and situated on a gossamer net of mycelium. 

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



Actinonema rosae Lib. (Asteroma radiosum Pr.). 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 Allesch. On living leaves of the ash. 



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

 Viburnum Opulus. 



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

 and Chaerophyllum hirsutum. 



Darluca. 



Darluca genistalis (Fr.). Ou living leaves of Cytisus sagiltalis. This may, 

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

 observed, just as Da7: filum. occurs ou several Uredineae. 



Diplodina. 



Similar to Biplodia, but having colourless conidia. 

 D. castaneae Prill, 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. 



' Allesoher, Iledwigia, 1894. 



Trillieux et Delacroix, BiUl. soc. mycol. de France, 1893. 



