112 NORTH AMERICAN FLORA [VoLUME 7 
DISTRIBUTION : Massachusetts to Nebraska, Utah and northward ; Mexico; also in Europe. 
ILLUSTRATIONS: Ber. Deuts. Bot. Ges. 17: fl. 26; Beitr. Krypt. Schweiz 22; 7, 322-326. 
ExsiccaTi: Ellis, N. Am. Fungi 1437; Ellis & Ev. Fungi Columb. 1629, 2232. 
7. HYALOPSORA Magn. Ber. Deuts. Bot. Ges. 19: 582. 1901. 
Cycle of development imperfectly understood ; telia and two other spore-forms known, 
for convenience called aecia and uredinia. No evident alternating phases observed. Aecia 
and uredinia subepidermal, telia within epidermal cells. 
Aecia barely protruding through the epidermis, irregularly dehiscent, roundish, bullate, 
without peridium. Aeciospores borne singly on pedicels, broadly obovate; wall colorless, 
minutely verrucose, pores obscure. 
Uredinia similar to the aecia, but with depressed globoid peridium. Peridium deli- 
cate, with polygonal cells above and elongate cells at sides, the lateral cells usually 
reinforced with shorter cells outside. Urediniospores borne singly on pedicels, resembling 
the aeciospores, but usually smaller and thinner-walled, minutely verrucose, pores indis- 
tinct, equatorial. 
Telia effused, indehiscent. Teliospores globoid, about four-celled by vertical inter- 
secting septa; wall colorless, smooth, thin. 
Type species, Uvedo Aspidiotus Peck (on Phegopteris Dryopteris). 
Urediniospores quite regularly obovate to globoid ; aecia usually present. 
Spores large, wall rather thick. 1 
Spores small, wall thin. 2 
Urediniospores irregularly elongate-obovate to globoid ; aecia usually absent. : 
Spore-wall appearing smooth. 3. H. laeviuscula. 
Spore-wall clearly verrucose. 4. H. Chetlanthis. 
. A. Aspidiotus. 
. H. Polypodti, 
1. Hyalopsora Aspidiotus (Peck) Magn. Ber. Deuts. 
Bot. Ges. 19: 582. 1901. 
Uredo Polypodit g Polypodti-dryopteridis Moug. & Nestl.; DC. Fl. Fr. 6: 81. 1815. 
Uredo Aspidiotus Peck, Ann. Rep. N. Y. State Mus. 24: 88. 1872. 
Pucciniastrum Aspidiotus Karst. Bidr. Finl. Nat. Folk 31: 143. 1879. 
Caeoma Aspidiotus Peck, Bull. Torrey Club 10: 62. 1883. 
Melampsorella Aspidiotus Magn. Ber. Deuts. Bot. Ges. 13: 288. 1895. 
Hyalopsora Polypodii-dryopteridis Magn, Hedwigia Beibl. 41: 224. 1902. 
I. Aecia amphigenous, rounded, small, 0.2-0.5 mm. across, bullate, yellow, tardily 
dehiscent ; aeciospores ellipsoid or polyhedral, large, 30-40 by 40-55 #, wall thick, 2.5-3.5y, 
colorless, indistinctly verrucose, appearing smooth when wet, pores 6-8, scattered. 
II. Uredinia amphigenous, irregularly scattered, round, small, 0.2-0.5 mm. across, 
golden-yellow, soon dehiscent by rupture above, somewhat pulverulent; peridium rudimen- 
tary, delicate, urediniospores ellipsoid or oval, 19-24 by 29-354; wall colorless, medium 
thick, 1.5-2, minutely verrucose, pores 4, equatorial. 
III. Teliospores in epidermal cells, globoid, often irregular, 25 by 21-35, usually 
4-celled, but frequently 3- or 5-celled; wall thin, 14, colorless, smooth. 
On POLYPODIACEAE : a 
Phegopteris Dryopieris (1,.) Fée (Polypodium Dryopieris I,.), Michigan, Montana, New 
Hampshire, New York; Alaska; British Columbia. . ; 
TYPE LOCALITY : Catskill mountains, New York, on Phegopieris Dryopleris. 
DISTRIBUTION : New Hampshire to British Columbia, and northward; also in Europe. 
ILLUSTRATIONS : Ber. Deuts. Bot. Ges. 13: fl. 27; Beitr. Krypt. Schweiz 2?: /, 308. 
Exsiccati: Thiim, Myc. Univ. 250, Sydow, Ured. 1899. 
2. Hyalopsora Polypodii (DC.) Magn. Ber. Deuts. Bot. 
Ges. 19: 582. 1901. 
Uredo linearis g Polypodii Pers. Syn. Fung. 217. 1801. 
Uredo Polypodti DC. Fl. Fr. 6: 81. 1815. 
Uredo Aspidii Poll, Giorn, Fis. 9: 182. 1816. 
Caeoma Filicum Link, in Willd. Sp. Pl. 62: 36. 1825. 
I. Aecia hypophyllous, similar to the uredinia; aeciospores globoid or obovate-globoid, 
somewhat angular, 18-25 by 27-33; wall nearly or quite colorless, medium thick, 2-34, 
minutely verrucose, appearing smooth when wet, pores 6-8, scattered. 
