Didymium. 225 



Far. costatum, Mass. 



Sporangia covered uniformly with minute particles of lime, 

 not becoming broken up into large, distinct patches; stem white, 

 variable in length, expanding at the base into a small hypo- 

 thallus with prominent radiating ridges. Stem sometimes very 

 short, sunk in the umbilicus or entirely absent. 



Didymium squamulosum, ft. leucopus, y. costatum, Host., Mon., 

 p. 159 ; Cooke, Myx. Brit., p. 33 ; Sacc., Syll, no. 1301. 



JExsicc. Rab., Fung. Eur., 367 (as Didymium praecox, De 

 Bary) ; Fuckel, Fung. Rhen., 2690 (as Didymium squamulosum 

 y. costatum} ; Rab.-Wint., Fung. Eur., 2675 (as Didymium Nea- 

 politanum, Ces.). 



On leaves, wood, &c. 



Distinguished from the type by the white crust of the pileus 

 not becoming broken up into patches, and by the markedly 

 costate hypothallus. Somewhat resembling Didymium depres- 

 sum, Fr., which however is readily distinguished by the much 

 larger and more coarsely warted spores. 



Britain (Epping Forest, Chiselhurst, Kew, Carlisle) ; France ; 

 Germany; Austria. 



(Rostafmski's Synonyms.) 



Eeticularia hemispherica, Bull., p. 93 (1791). 

 Diderma sguamulosum, A. and S., t. 4, f. 5 (1805). 

 Didymium globosum, v. stipitatum, Schwarz., Ac. Holm., p. 



114 (1815). 



Licca stipitata, D. C., Fl. Fr.;No. 670 (1815). 

 Tubulina pedicellata, Poir., Ency., v., p. 373. 

 Cionium farinaceum, Spr., Syst., iv., 528 (1827). 

 Didymium herbarum, Fr., S. M., iii., 120 (1829). 

 Didymium leitcopus, Fr., S. M., iii., 121 (1829); Cooke, Hdbk., 



No. 1127. 



Didymium costatum, Fr., S. M., iii., 118 (1829). 

 Didymium liceoides, Duby, Bot. Gall., ii., 864 (1830). 

 Didymium Jilamcntosum, Wallr., Fl. Germ., No. 2187 (1833). 



