Seaver: Observations on Herpotrichia nigra 211 
The Mytilidion is closely related to, if not identical with 
Mytilidion fusisporum (Cooke) Sacc., a species which has been 
reported on branches and bark of spruces and firs. Cooke’s 
species is said to have spores 50 fi long, while the spores of our 
species have never been found to exceed 40 /jl and are often not 
more than 30 /x. Having seen no authentic specimen of Cooke’s 
species, it is impossible to know how much importance to attach to 
this apparent difference in the size of the spores. Our specimens 
have been doubtfully referred to that species. 
The recent appearance of the description of a new species of 
Herpotrichia by Weir in the Journal of Agricultural Researchh 3 .s 
attracted the attention of the writer since the spores of his species 
were practically identical in size and form with those of the 
Mytilidion which has been so frequently found associated with 
Herpotrichia nigra. From the facts in hand the writer is inclined 
to believe that Weir’s supposed new species is based on the com- 
bined characters of two different plants, the mycelial and perithe- 
cial characters being those of the well-known Herpotrichia nigra 
while the ascus and spore characters are those of the Mytilidion. 
Tills suspicion has been strengthened by recent studies of our 
collections of Herpotrichia nigra which shows practically every 
specimen examined to be accompanied by the Mytilidion, the 
abundance of the latter species varying considerably in different 
specimens. To add to the difficulty the perithecia of the Mytilidion 
are often overrun by the mycelium of the Herpotrichia so that 
the perithecial characters are obscured. Not only has the My- 
tilidion been found on spruce needles associated with Herpotrichia, 
but it has also been found on pine needles associated in the same 
way with Neopeckia Coulteri. 
Weir’s drawings illustrate very well the spore characters of the 
three species, Neopeckia Coulteri, Herpotrichia nigra and the 
unnamed species of Mytilidion except that the spores of 'the las\ 
are not always 5-septate as indicated in his drawings but are ofte” 
6-septate and occasionally even 7-septate. The spore measure- 
ments are usually within the limits given by Weir, but spores are 
occasionally found as long as 38-40 /x. The color is pale-brown, 
as indicated by him. 
New York Botanical Garden. 
