Shear and Dodge : Patellina, Leptothyrium, Peziza 157 



identical in the structure of the pycnidium and scarcely differs 

 from S. concava in any way except in the shape and size of the 

 spores. 



Leptothyrium macrothecium Fckl. Fuckel ( 1870) de- 

 scribed this species from leaves of Rosa, Potentilla, Quercus, and 

 Rubus in Germany. Specimens in his exsiccati, Fun. Rhen. Nos. 

 551, 553 and 1714 on leaves of the first three hosts respectively 

 and others on leaves and stems of Rubus from Fuckel's her- 

 barium have been examined. The specimens are identical with 

 Sclcrotiopsis concava (Desm.), the pycnidial form of Pczizella 

 lythri found in America on a great variety of hosts. Leptothy- 

 rium macrothecium has been figured by Saccardo (1881) and by 

 Laibach (1908). The latter has an excellent figure of a section 

 of a pycnidium showing the character of the thick wall and a 

 palisade-like layer of conidiophores extending across the base of 

 the pycnidium. Laibach makes no mention of finding a conidial 

 fungus corresponding to the Haincsia stage associated with the 

 pyenidia. 



No. 552, Fun. Rhen. was originally labeled Leptothyrium ma- 

 crothecium f. rhois in Fuckel's herbarium. This form resembles 

 the species superficially except that the surface of the pycnidium 

 is somewhat rugose. The spores are 14-15 /x long. Noting these 

 differences Fuckel later (1870) referred the fungus to L. rhois 

 West. Westendorp's plant, however, as already pointed out (p. 

 154) is quite different from Fuckel's. Fuckel's form Rhois is 

 not a Gloeosporium as stated by Saccardo (1884). The fungus 

 agrees in all morphological characters except spore measurements 

 with L. macrothecium and seems undoubtedly congeneric with it. 

 Typical L. macrothecium has been frequently found on both 

 native and introduced species of Rhus about Washington, but we 

 have never found the form with large spores described by 

 Fuckel. The occurrence of this second species of pycnidial fun- 

 gus on Rhus seems to justify the belief that it belongs to a dis- 

 comycete congeneric with Pezizella lythri and probably has a 

 conidial form similar to Hainesia lythri. A pycnidial fungus 

 very similar, if not identical, with this is Pilidium acerinum Kze. 

 which occurs in Europe on Acer and Carpinus leaves. It has not 



