4o8 PLANT DISEASES 



(1880). — Sori pulvinate, minute, often densely gregarious, 

 orange ; spores subreniform, convex, free portion warted, 

 remainder smooth, 30-35 X 10-12 jx. 



The sterile cysts mentioned by the authors are only 

 young, still smooth spores ; the same occurs in H. 

 vastatrix, when the pustules are examined while young. 



Hemileia canthii, Berk, and Broome, /ourn. Lititi. Soc. 

 {Bot.) xiv. p. 93 (1875). — Sori scattered on pale spots, 

 hypophyllous ; spores subreniform, free convex surface 

 warted, remainder smooth, 25-30 X 10-12 //. 



Cronartium, Fries. — Aecidia produced on conifer leaves, 

 pseudosporidia elongated, aecidiospores concatenate ; 

 uredospores included in a pseudoperidium, brown; teleuto- 

 spores i-celled, aggregated into a column which springs 

 from the sorus of uredospores. 



Cronartium ribicolum, Deitr., Af'ch. Nattirk. Liv. Esth. 

 und K2irla7ids, ii. p. 287. — Aecidiospores large, epispore 

 warted, one part smooth ; sori of uredospores forming 

 pustules, orange-rufous, minute, rounded, pseudoperidia 

 hemispherical, perforated at the apex, uredospores ellipti- 

 cal or ovoid, 19-35X14-22 /x, epispore hyaline, aculeate, 

 contents orange ; teleutospores forming a columella up to 

 2 mm. high, curved, yellowish-rufous. 



Cronartium asclepiadeum, Fries, Obs. Myc, i. p. 220. — 

 Aecidiospores 22-26, rarely 30X16-20 //, epispore partly 

 reticulated, partly warted; uredospore sori hypophyllous, 

 scattered, brown ; uredospores variable in form, echinate, 

 16-32x12-18 /x, pale orange; columella of teleutospores 

 terete up to 2 mm. long ; teleutospores oblong, truncato- 

 obtuse, 12 /x broad ; sporidiola globose, smooth, pale 

 yellow, 



