436 Arthur and Kern : Peridermium 



thicker and rather coarsely verrucose ; aeciospores broadly ellip- 

 soid or globoid, 18-22 by 20-30 «, wall thin, 1-1.5 ft, densely and 

 rather coarsely verrucose ; contents colorless. 



On Abies balsamea (L.^ Mill., Kings Ravine, Mt. Adams. New 



W. G. Farlezviva Ellis. N. A 



My 



Minnesota, July 24, 1886, E..W. D. Holway 208 ; Mt. Moosi- 

 lauke, New Hampshire, August 26, 1884, Miss Clara E. Cum- 

 wings ; Ellis River, New Hampshire, August, 1889, L. M. Under- 

 wood; Catskill Mountains, Greene County, New York, August, 



J.F.Ji 



Agric.) ; 



Newfoundland, 1894, Robinson & Schrenk ; Summit of Mt. Wash- 

 ington, New Hampshire, August 16, 1895, E. T. Harper 268 ; 

 Neebish Island, Michigan, August 25, 1899, E. T. Harper jjj ; 

 Adirondack Mountains, New York, no date, Chas. H. Peek ; Dela- 

 ware County, Iowa, 1890, collector unknown, communicated by 

 Prof. T. H. Macbride. 



On Abies grandis Lindl., southern slope of Mt. Paddo, Wash- 

 ington, October 31, 1903, W. N. Suksdorf 965. 



This species is especially characterized by white spores, which 

 also occur in Aeeidium psendo-eolumnare Kiihn. The probable 

 identity of the two forms was pointed out by Farlow,* and our 

 studies confirm this opinion. The only difference we could detect 

 was that the peridial cells were a little more coarsely verrucose in 

 the American specimens. But our European material for the study 

 was scanty, and even this seeming difference may not be constant. 

 Should the two be found to be identical, Kuh^s name should be 

 added to the above as a synonym, as it was published about ten 

 years later than the one by Peck. 



29. Peridermium Laricis (Kleb.) nom. nov, 



Aeeidium Laricis Kleb. Zeits. Pflanzenkr. 9:18. 1899. 



0. Pycnia amphigenous, rather numerous, scattered, incon- 

 spicuous, subcuticular, pale-yellow, flattened-conical, 50-65 u in 



diameter by 20-30 ft high; pycniospores oval, 1.5—2'/! long, 

 abundant. 



1. Aecia from a limited mycelium, hypophyllous, solitary or 

 in rows on one or both sides of the midrib, flattened laterally, or 



* Proc. Am. Acad. 20 : 322. 1 885. 



