208 NORTH AMERICAN Fl,ORA [VoivUMK 7 



29. Gymnosporangium corniculans Kern; Arth. 



Mycologia 2 : 236. 1910. 



0. Pycnia epiphyllous, rather few, gregarious, in small groups 0.5-1 mm. across, on 

 discolored spots, rather prominent and conspicuous, honey-yellow becoming blackish, 

 slightly fiattened-globose, 130-175 ju in diameter by 130-160 ju high; ostiolar filaments 

 50-80 M long. 



1. Aecia hypophyllous, gregarious, crowded in irregular or sometimes annular groups 

 2-5 mm. across, on discolored hypertrophied spots, cylindrical or horn-shaped, acutish at 

 apex, 2-3.5 mm. high, 0.3-0.5 mm. in diameter; peridium not or only rarely rupturing at 

 apex, very tardily dehiscent by longitudinal slits along the sides ; peridial cells usually seen 

 in face view, not hygroscopic, remaining straight when wet, broadly lanceolate, 16-23 by 

 64-96 ju, rhomboidal in side view, 18-25 ju thick, the outer wall rather thin, 1.5-2ju, smooth, 

 the inner and side walls rather thick, S-7 n, moderately verrucose with oval or roundish 

 papillae and a few rather delicate elongate papillae interspersed, the papillae becoming 

 shorter and more oval toward the outer wall ; aeciospores globoid, 20-26 by 23-32 ^u ; wall 

 dark cin nam on -brown, rather thick, 3-4/*, very finely verrucose, appearing nearly smooth, 



the pores 8-10, scattered. 



On Malaceae : 



Atnelanchier canadensis (I,.) Medic. i^A. Boiryapium DC), Illinois, Iowa, Massachusetts, 



Penns3?lvania, Vermont, West Virginia. 

 Amelanchier erecta Blanchard, Michigan. 



Amelanchier intermedia Spach (>4. Boiryapium Hook., not DC), Illinois, New York. 

 Amelanchier oblongifolia (T. & G.) Roem., Michigan. 

 Amelanchier sanguinea (Pursh) Lindl. {A. rotundifolia Roem.), Ontario. 



III. Telia caulicolous, from a perennial mycelium, appearing on irregularly lobed, 

 gall-like excrescences 2-15 mm. or more in diameter, unevenly disposed, often separated 

 by the scars of the sori of previous seasons, conical or cylindrical-acuminate, 1.5-2 mm. in 

 diameter at the base by 3-5 mm. high, dark chestnut-brown becoming yellowish and 

 pulverulent by germination; teliospores 2-celled, ellipsoid, 18-21 by 35-50 m, usually 

 rounded both above and below, slightly or not at all constricted at the septum, slightly 

 enlarged near the septum in one or two places owing to the presence of hyaline thicken- 

 ings over the germ-pores ; wall light cinnamon-brown, thin, 1-1.5/*, hyaline thickenings 

 about 1-1. 5/i, the pores 1 or 2 in each cell, near the septum; pedicel uniform, 4-6/i in 

 diameter, rather long. 



On Juniperaceae : 



Juniperus horizontalis Moench (/. prostrata Pers.), Michigan. 



Juniperus virginiana L., New York. 

 Type locality : Iceland, Michigan, onjunipents horizontalis. 



Distribution : From Vermont and Massachusetts west to northern Illinois and eastern Iowa. 

 Illustrations : Bull. N. Y. Bot. Card. 7 : 472, /. 33 ; pi. 160 J. 64. 



Exsiccati : Ellis & Ev. N. Am. Fungi 2715; Ellis & Ev. Fungi Columb. 1827; Seym. & Earle, 

 Econ. Fungi 2^^, b. 



30. Gymnosporangium floriforme Thaxter ; Kern, Bull. Torrey 



Club 35: 503, 1908. 



Roestelia Jlaviformis Atk.; Underw. & Earle, Bull. Ala. Exp. Sta. 80 : 218, hyponj^n. 1897. 

 Gymnosporangium flaviforme Earle, Contr. U. S. Nat. Herb. 6: 186, hyponym. 1901. 

 Aecidium Jiaviforme Farl. Bibl. Index 1 : 44, hyponyra. 1905. 



0. Pycnia epiphyllous, numerous, gregarious, more or less crowded in irregular groups 

 1-5 mm. across, on thickened discolored spots 5-10 mm. or more across, prominent, con- 

 spicuous, punctiform. honey-yellow becoming blackish, globoid or somewhat flask-shaped, 

 150-175 ju in diameter, 130-160 /i high; ostiolar filaments up to 50 ^ long. 



1. Aecia hypophyllous, rather widely separated in oblong-annular groups 2-6 mm. 

 across, on thickened discolored spots 5-10 mm. or more across, at first cylindrical, 1-1.5 mm. 

 high, 0.2-0.5 mm. in diameter; peridium splitting extremely early and becoming rather 

 finely fimbriate to the base, strongly revolute ; peridial cells usually seen only in side view, 

 long and narrow, 10-14 by 65-85 ^u, hygroscopic, becoming somewhat curved when wet, 

 the outer wall smooth, rather thin, 1.5-2 ju, the inner wall rugose, moderately thick, 4-5^, 

 the side walls rather closely rugose with ridges running from the inner side transversely and 



