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IOWA ACADEMY OF SCIENCES 
is associated, been introduced here. Of North American corticolous forms 
may be mentioned Peridermium harknessi, Moore, which forms nodes 
covered with confluent masses of aecidia on Finns ponderosa, Finns radv- 
ata, P. sahiniana and P. contorta, and Periderminm cerebrum^ Peck, on 
Finns rigida. Of North American acicolous forms may be mentioned 
Periderminm harknessi, Moore, which forms nodes covered with con- 
fluent masses of aecidia onPinns ponderosa, Finns radiata, P. sahiniana, 
and P. contorta, and Periderminm cerebrum, Peck, on Finns rigida. Of 
North American acicolous forms of Peridermium the most common is per- 
haps identical with Peridermium ohlongispomm, Fuckel. This is not 
uncommon on Finns rigida in early summer, but the teleutosporic form 
with which it is said to be united in Europe, Coleosporinm senecionis, 
Persoon, is certainly very rare here, although it has been noticed on 
liiCnecio vulgaris near Providence, Rhode Island. Besides the Rusts be- 
longing to the genus Peridermium, Coleosporium pini, Galloway, attacks 
the leaves of Pinus virginiana in the middle states, causing bands of yel- 
low discoloration and a premature shedding of the leaves. Unlike other 
rusts of pine trees, this species is a teleutosporic and not an aecidial 
form. The rusts which are often found in abundance on conee of various 
pine trees, especially in the southern and western states, need further 
study.” 
Three species of Peridermium are common in the Rocky mountain 
country at least the regions visited by the writer in the Big Horn moun- 
tains, Medicine Bow mountains and in the Uintah mountains. These 
species may be referred to P. elatinum on AMes sudalpina, P. 
coloradoense on Picea engehnannii and P. parryana, P. cerehrum on 
Finns murrayana. Calytospjora goeppertiana is also abundant and if 
the conclusions of the European investigators are correct we ought to find 
also P. columnare. The aecidia of the latter species are sufficiently dis- 
tinct to attract attention, but they have not been observed . According 
to Dr. Farlow, P. halsamenm, closely resembles P. colnmnare of European 
authors. Holway found P. Mlsamenm on Abies balsamea near Yer- 
millian Lake, Minn, in 1886, No. 208, specimens having been placed at my 
disposal by Prof. MacMillan. It may also be looked for on A. snbalpina 
in the Rocky Mountains. Peridermium engelmannP Thum. was de- 
scribed from Colorado specimens found on the cones of Picea engel- 
manni. The species has not been seen hy the writer. It is said to be 
closely allied to P. co7iorum Thum. 
Pekidermium Cerebrum, Peck. 
History. This fungus was described by Peck^ from specimens found 
near Center, New York on Pinus rigida collected by Dr. Lintner. In 
Saccardo’s^ Sylloge Fungorum it is reported from New York, New Jersey, 
Pennsylvania and District of Columbia. The species was first found in 
this country by Schweinitz^ who described it as P. pineneum. Underwood 
L Die Blasenrost-pilze. 314. 
2. Rep. N. Y. Sate Mus. of Nat. Hist. 25 : 91. 
3. 1. c. 7: 837. 
4. Jour. Myc. 7 : 44. Dot. Gazette 22 : 435. 
