10 SALMON: SUPPLEMENTARY 
can be most easily seen in U. polychacta. In this species the very 
numerous crowded appendages spread widely, and attach the re- — 
versed perithecium by a film-like layer spreading beyond the di- — 
ameter of the perithecium on every side. The mucilaginous break- 
ing down of the walls of the appendages is very evident here, and 
the reattachment of the perithecium is as firm as that caused by 
the penicillate cells of Phyllactinia. 
In U. circinata, also, if reversed perithecia are placed on a damp 
leaf, they will be found subsequently to have become attached to 
it by their appendages. 
This phenomenon of the spontaneous freeing of the perithe- 
cium and its subsequent reattachment by the appendages has been 
the cause, I believe, of leading systematists into several curious 
errors. The first case that may be mentioned is that of ‘ Unci- 
nula Columbiana Selby,” on Scutellaria laterifora from the United 
States. This fungus, as I pointed out in my monograph, p. 86, agrees 
exactly in all its characters with U. salicis. VU. salicis is only known 
to grow on species of Salix and Populus, and 1 suggested at the 
time that its presence on the Scuéellaria was perhaps accidental. 
I feel now little doubt that we have here an instance in nature of 
the perithecia of U. salicis becoming attached by their appendages 
in the manner described above to a foreign substratum, in this case 
the leaves of a herbaceous plant. In a second case it seems quite 
certain that reversed perithecia of U. salicis attached by their ap- 
pendages have been under observation. I refer to the “ U. salicis 
var. epilobi”’ of Vestergren (Bot. Notiser, 1897: 256), which 
was described as growing at Upsala on Epilobium angustifolium, 
(see monograph, p. 87). In the description Vestergren remarks : 
“The most obvious presumption would be that the perithecia of 
the Uncinula in question had been transferred by the wind to the 
Epilobium from, e. g., some Salix bushes growing in the neighbor- 
hood. Apart from the fact that there were none of the usual 
host-plants of U. saficis in the neighborhood, one must quite re- 
ject this presumption when one observes (under a slight micro- 
scopic magnification) how firmly the perithecia of the var. epi/obit 
are fixed to the substratum by means of the appendages radiating 
on all sides.” We may, I think, safely infer here that groups of — 
perithecia of U. salicis must have been blown on the Epilodium, 
and adhered by the appendages in the manner described above. 
