Arthur and Kern : Peridermium 421 



i 



ii. Peridermium Harknessii Moore, Bull. Calif. 



Acad. Sci. I : ^y. 1884 



0. Pycnia unknown. 



1. Aecia caulicolous, appearing on ellipsoid, oblong or some- 

 times nearly globoid swellings, scattered or often in groups and 

 confluent, yellow at first fading to white, bladdery, large ; peridium 

 rupturing irregularly, soon falling away entirely, about two cells 

 thick, outer surface smooth, inner irregularly verrucose, cells 



oundish or irregularly compressed, walls very thick, radially stri- 

 ate, lumen small ; aeciospores ellipsoid or obovate, 15-21 by 23- 

 31//, wall colorless, uniformly thick, 2.5-3.5 /i, finely verrucose, 

 with smooth area at base often extending up one side. 



On branches of Pi mis insignis Dougl., Menlo Park, California, 

 May 6, 1893, IV. C. Blasdale (specimen in herbarium of E. W. 

 D. Hoi way). 



On branches of Pinus Murrayana Oreg. Com., Yosemite Val- 

 ley, California, May 29, 1895, W. C. Blasdale (specimen in her- 

 barium of E. W. D. Holway) ; Dragoon, Washington, no date, 

 H. von Schraik (specimen at Miss. Valley Lab., St. Louis) ; Boze- 

 man, Montana, September, 1903, collector unknown (two speci- 

 mens at Miss. Valley Lab., St. Louis, each about 60 cm. long and 

 8-10 cm. thick). 



On branches of Pinus ponderosa Dougl., Colfax, California, no 

 date, H. W. Harkness (specimen in herbarium of N. Y. Bot. Gar- 

 den) ; Dragoon, Washington, no date, H. von Schrenk (specimen 

 at Miss. Valley Lab., St. Louis); Long Pine, Nebraska, May 13, 

 1889,/. M. Bates j 70 (specimen in herbarium N. Y. Bot. Garden). 



On branches of Pinus contorta Dougl., New Metlakahtla, 



Alaska, June 4, 1899, Wm. Trelease 667 (specimen in herbarium 

 of Missouri Bot. Garden, St. Louis). 



This species appears to be very abundant in the Rocky Mt. 

 region, often doing much damage, especially to seedling trees. The 

 galls are usually large, often one to two feet in diameter. The 

 large size is doubtless one reason why the species is so poorly 



represented in herbaria. 



1 2. Peridermium fusif orme sp. no v. 



0. Pycnia unknown. 



1. Aecia caulicolous, forming fusiform swellings, 2-6 cm. in 

 diameter by 5-25 cm. long, on comparatively small branches, 



