167 
under M,. sphaeroideum several species, including, however, 
among them J/. ayiocarpum on Alnus, 
It will clear up this confusion if it is agreed to consider M. 
apiocarpum as belonging typically to Alnus, and M. sphaerot- 
to J¢hamnus. Whether the two are really distinct is another 
question which cannot yet be answered. Link obviously con- 
The description and synonymy will then be as follows :— 
Pustules scattered, about 1 mm. in diameter, conical, rather 
prominent, very black, with a central white stroma. Spores oblong 
or ovoid, obtuse at both ends, especially above, with one or two 
guttules, smoky-brown, semi-pellucid, 10-13 x 5-6 mu, appearing 
often falsely 1-septate and didymous, 7.e., subconstricted at the 
middle. 
On twigs of Alnus. Not uncommon; specimens found by the 
late Dr. J. W. Ellis at Bridgnorth are exactly M. didymoideum, 
Syn.—M. sphaeroideum, Sacc. Syll. iii. 755 (non Link); Fung. 
Ttal. tab. 1079. 
M. didymoideum, Vestergr. in Hedwig. 1903, xlii. 82. 
No British specimens of the fungus on Rhamnus (A. sphaerot- 
deum) have so far been seen. It will be noted that Saccardo 
appears to found his reference of M. sphaeroideum to Alnus on 
the quotation of that name by Mougeot as a synonym of his 
Stilbospora microsperma; Fuckel had expressed the same idea 
previously. se 
All the foregoing species are closely similar; the next group 
is distinguished by possessing much larger spores. It may be 
divided into three forms, which occur on Hornbeam, Walnut, and 
Beech respectively. The two first are said to be very similar: all 
of them may perhaps wander to other hosts. 
6. Melanconium magaum, Berk., Outl. p. 324 (1860); Sace, 
Syll. iii. 753. 
Naemaspora magna, Grev. Scot. Crypt. Flor. tab. 349 (1823). 
Stilbospora magna, Berk. Eng. Flor. v. 357 (1836). 
Subspecies 1. M. carpineum, comb. nov. 
Sphaeria carpina*™ (? misprint for west ao Bs oh Fung. tab. 
376 (1803). Naemaspora carpinea, Baxt. no, 76. 
pasa aeta or oblong, thick-walled, dark greyish-brown, 18-25 
x 10-11 p. 
* Not Carpini, as usually quoted. 
