IOWA ACADEMY OF SCIENCES 
101 
JHistouv. This fungus was described by Albertini and Schweinitz’^ 
as Aecidium ahietinum from Listiania and placed in the genus Periderm- 
ium by Von Thumen, but most mycologists have referred the fungus to 
Aecidium abietinum Alb. & Schw. Dr. Parlow makes the following 
interesting account on the P. abietinum found in the White Mountains. 
“Of the three forms mentioned, P. abietinum in confined to the higher 
mountains, being found in great abundance on Abies nigra; P. balsameum 
infests Abies balsamea, and extends from an altitude of about 4,000 feet 
to the level of the Androscoggin; and P. peeJcii which attacks Abies cana- 
densis, is confined to the base of the mountains. Every one who has 
climbed to any of the higher mountains will recollect, with anything but 
pleasure, the entangled growth of dwarf Abies nigra, which forms a belt 
just below the region of bare rocks. It is in this dwarf growth the P. 
abietinum abounds on all the mountains I visited, namely Washington, 
Adams, Moriah and Success. I first found the aecidia in King’s Ravine 
in the third week in August, when the peridia were just opening; but 
the fungus ^mes not attain perfection until two or three weeks later, and 
it was so abundant on Moriah and Success in the third w^eek in Septem- 
ber that in attempting to penetrate the thicket, I was completely covered 
by the cinnibar-colored spores which were discharged in showers. Nearly 
every leaf on the smaller branches is attacked by the fungus and dis- 
colored. It is not, to be supposed that the fungus attacks the larger trees 
of Abies nigra lower down on the mountains at an earlier date, and that 
what I saw was only the later development near the summit. The change 
is not gradual; but one comes suddenly upon immense quantities of the 
Pcridcrmium as soon as the dwarf form of the Abies is reached. I am 
unable to distinguish this Peridermium from the P. abietinum (A. & S.) 
of Europe as seen in Fung. Eur., No. 1676, which is considered to be the 
aecidium of Ghrysomyxa rhododendri (DC.). Of the original Aec. aMe- 
tinum (A. S.), two forms have been in later times recognized as stages 
of Chrys. rhododendri and G. ledi, respectively. The two forms are dis- 
tinguished by slight differences in the peridial cells, difficult to recognize 
in dried specimens. As already remarked, our form resembles very closely 
No. 1676, Fung. Eur., which is cited by Winter as belonging to Ghrys. 
rhododendri. Our form was called by Peck, P. decolorans, in the twenty- 
seventh report of the New York State Museum, and later it was called P. 
abietinum var. decolorans in Thuemen’s'^ “Blasenrost-pilze der Coniefren.” 
I examined with great care the Rhododendron lapponicum and Ledum lati- 
folium near the dwarf spruce, but found no trace of Ghrysomyxa. My 
search was so thorough that I think it safe to say that at that date there 
was no Ghrysomyxa on any of Voq Ericaceae in the localities examined.” 
This fungus whs distributed by Ellis and Everhart* as P. abietinum f. 
engetmanni and under the same name from northern Colorado collected 
by Prof. Crandall. DieteP had made the Ellis and Everhart specimen 
1. Conspect. Fung. 126. pi. 5. f . 5 . 
2. Appalachia 3 : 240. 
3. Die Blesenrost — pilze d. Coniferen Mitth. forstl. Versuchsw. Oestr. 314. 
4. Pimg. Columb. 876 2 : N. Am. Fung. 2223. 
5. Die Nat. Pflanzenf. 1 : 78. 
