Exobasidium 



THELEPHORACE/E 



423 



normally tetrasporous, but spores sometimes varying in number from 

 one to five. The hymenial cells are borne on vegetative hyphse 

 which grow in the cellular tissue of the host and form a loose stratum 

 on its external surface. Spores ovate to elongate-oval, continuous, 

 rarely becoming septate, colourless. (Fig. 103.) 



Most nearly allied to Corticium, but differing in the absence of 

 a sporophore or subiculum and in being parasitic. Exoascris, an 

 Ascomycetous fungus, sometimes grows in company with Exobasidium. 



Species 1899, 1900 



1899. E. Vaeeinii Woron. (from its growth on Vacdnium and its 



allies) a b c. 



Innate, effused, usually orbicular or elongate, often confluent. 

 Hym. on under surface of leaves and round stems, pale rose, 

 covered with a white bloom. 



June-Aug. \ in. Red or purple patches occur on the upper surface of the 

 leaves, opposite to the portion occupied by the fungus below. 



1900. E. Rhododendri Cramer (from its growth on Rhododendron) a c. 

 Forming gall-like bullate excrescences, at first pale, then reddish 



and shining on stems, petioles and under surface of leaves. 



On Rhododendron ferrugineum, ft. hirsntum, R. Wilsonii. July. I in. 

 Insects, mites, etc., are often found in the gall-like swellings of 



Exobasidium. 



LXXXIX. CYPHELLA Fr. 



(From the usual shape, like a small goblet, Gr. kup/ws.) 



Usually small, sometimes almost minute, somewhat membranous, 

 cup-shaped, rarely plane, adnate from a central or oblique point, 

 sometimes with a stem and pendulous. 

 Hymenium within the cup or disc. Basi- 

 dict tetrasporous, rarely bisporous. Spores 

 subovate. (Fig. 104.) 



Closely allied to Solenia. C. per- 

 pusilla is intermediate. Owing to the 

 strong external resemblance in many 

 Cyphcllce to certain small species ofPeziza, 

 a genus of Ascomycetous fungi, it is 

 necessary to examine microscopically 

 the hymenium of some of the species 

 for the decisive characters of basidia 

 or asci. C. faginca Lib. is British, 

 but it is an Ascomycete. 



Species 19011922 



Stipitate. 



Sessile or subsessile. 



Spores hyaline. 



Spores coloured. 



19011905 



19061918 

 19191922 



Fig. 104. A, Cyphella. brunnea 

 Phill., X 2. B, ditto with c, sec- 

 tion, X 10. D, basidium and spores, 

 X 500. 



