lAliLDEWS, RUSTS AND SMUfS 
137 
Aecidia. On both sides of the leaves, usually sparingly 
scattered over the entire surface, rarely in circular or oblong 
groups, somewhat cylindrical cup-shaped, edge recurved, 
torn, whitish ; spores angularly globose, very minutely 
warted, orange, 16—24 p diam. 
Uredospores. Sori on both surfaces of the leaf, and on 
the stem, irregularly distributed, minute, circular, for a long 
time covered by the epidermis, brown ; spores subglobose 
or broadly elliptical, minutely warted, yellowish-brown, 
20—^30 p diam. 
Teleutospores. On both surfaces of the leaf, and on the 
stem, irregularly scattered, mostly minute, circular or elon¬ 
gated, rather compact, blackish ; spores oblong, elliptic- 
oblong or oblong club-shaped, tip generally rounded, and 
much thickened, base rounded or narrowed, smooth, brown, 
35—54 X 16—24 p, pedicel tinged brown, thick, somewhat 
persistent, rather long. 
Syn. Aecidiiim thesii, Desv. 
Uredo thesii, Duby. 
On leaves and stem of Thesium kumijiisum. Britain, 
Europe generally, and Siberia. 
IRIDACEAE 
IRIS 
Puccinia iridis, Wallr.: Plowr., Ured., p. 189. 
Uredospores. Sori on both sides of the leaf, most abundant 
on the under surface, scattered, or in lax clusters, circular 
or elongated, for a long time covered by the epidermis, 
at length powdery, minute, rusty brown ; spores globose, 
elliptical or ovate, echinulate, ochraceous, 20—35 x 16— 
26 p, epispore thick. 
Teleuto spores. Sori on the under surface of the leaf, 
irregularly scattered, or sometimes in clusters, forming 
lines, soon naked, blackish ; spores club-shaped or oblong, 
tip rounded and much thickened, sometimes pointed or 
truncate, darker, slightly constricted at the septum, base 
usually narrowed, smooth, pale brown, 30—52 X 15—25 p, 
pedicel tinged brown, persistent, about as long as the spore. 
Syn. Uredo iridis, D.C.; Berk. 
Uredo iridis, Plowr. 
Trichohasis iridis, Cooke. 
Puccinia truncata, B. and Br. 
On Iris pseudacorus, 1 . foetidissima, and on various 
cultivated species of Iris. Britain, Europe generally, 
Siberia, China, Japan, and N. America. 
