Phenomena attending Sphce^y^ia fraxinea. 171 



Ari. X. On some Phenomena attending Spkce'ria iraxmea. 

 By Electricus. 

 Sir, 



The specimen which I enclose for your inspection, I believe 

 to be one of the SphaeVia yVaxinea (/^. 4?.)? class Crypto- 

 gamia, order i^ungi, 

 L. Unfortunately, 

 I have not turned 

 my attention to this 

 tribe of plants ; and 

 I possess only the 

 edition of 1792 of 

 Withering's Bota- 

 nical Arrangement ; 

 I am therefore un- 

 able to determine 

 whether this subject 

 has now another ge- 

 neric name. Be 

 this as it may, the 

 annexed descrip- 

 tion is decisive, I 

 think, of the identity of the fungus. 



" Sphse^ia /raxinea. — Roundish, convex, black, dotted, 

 nearly sitting, pustular. ' Convex without ; substance within 

 consisting of a number of concentric layers, composed of mi- 

 nute tubes, or threads, pointing from the centre. Substance 

 hard ; covered with a thin bark, of a brownish black, some- 

 what wrinkled and rather glossy, grey within.' {Pay,) 

 * Very irregular in shape, from one half to more than an inch 

 in diameter. Pustules scarcely visible to the naked eye.' {RehL 

 Supp., i. 34.) This, which is very common, differs from the 

 S. maxima, in being more woody, and showing concentric 

 circles when cut. It is generally more completely sessile than 

 it is represented in the figures. 



" Lycoperdonyraxineum of Huds., &c. SphaeVia concen- 

 trica Bolt. — On ash trees when rotten, or in a decaying state, 

 and observed on no other tree." (Ray.) — With., vol. iii. 475. 



It is not on account of the mere curiosity of the species 

 that I now send it to you. Sir, although I am acquainted with 

 but one little, old, ash tree, in a state of decay (and that nearly 

 four miles from my residence), which produces these Sphae^- 

 riae from between the interstices of the bark ; but from the 

 singular phenomena which it exhibited during eight or ten 

 nights successively. Three or four of these Sphae^riae were 

 brought home one morning, and placed on the mantle-shelf: 



N 2 



