220 



MYCOLOGY 



are Dacryomyces, Guepinia, Calocera. Dacryomyces deliquescens forms 

 gelatinous, or gristly, lumps on tree stumps. Guepinia peziza is sapro- 

 phytic on oak stumps. Calocera viscosa is a branched upright form 

 suggesting the true coral fungi. 



Family 2. Exobasidiace^. — The mycelium of the fungi of this 

 family Hves parasitically in the chlorenchyma of many shrubs. The 

 fruit body is a thin basidial layer, which breaks out of the tissues of the 

 host. Each basidium develops four basidio- 

 spores; rarely 5 to 6 are formed. Some of the 

 species form galls on the stems, leaves and 

 flowers of ericaceous shrubs, such as species of 

 Vacciniiim, Rhododendron, Azalea, Andromeda, 

 etc. There are two genera: Exobasidium (Fig. 

 84), with eighteen species; and Microstroma, 

 with two species. Exohasidium caccinii (Fig. 

 84) develops swellings on the leaves of species 

 of Vacciniiim of a whitish-red color. Its 

 basidia are club-shaped with four sterigma 

 and four basidiospores. The basidiospores are 

 spindle-shaped, 14 to i6yu long by 2 to 3^ 

 broad, colorless and smooth. Exohasidium 

 rhododendri forms enlargements of the leaves 

 of species of Rhododendron of greater or less 

 size; colored white, or flesh-colored. Ex- 

 Fig. 84.— Floral gall ohasidium ledi occurs on Ledum in Finland. 



produced on flowers of 



huckleberry, Gaylussacia Exohasidium andromedcB grows on leaves and 

 resinosa, by Exohasidium ^^j^g ^f gpecies of Andromeda in Europe and 



vaccina. Note enlarged ° , '- ,.,. ... 



and swollen calyx. (Pine America. Exooasidium AzalecB IS found on 



mTT^' f ^i6T"^' ^' ■^" ^P^"^^ ^^ ^"^^^^^^ ^^ ^^^^^ America. E.v- 

 obasidium lauri forms widely spread, yellow 

 then brownish, horny, or club-like galls on the stems of the laurel in 

 Italy, Portugal and the Canary Islands. Exohasidium Warmingii 

 attacks the living leaves of Saxifraga aizoon in Greenland, Tyrol and 

 north Italy. 



Family 3. Hypochnace^. — The hymenium is cobwebby. The 

 basidia have two, four or six sterigmata. Cystidia are sometimes present. 

 Hypochnus occurs on old stumps, on leaves and on mosses. Tomen- 

 tella is another genus. 



