PAPERS GIVING RUSTS OF NORTH AMERICA. 251 



Represented by an original packet, containing part of one leaf 

 about 3 by 6 cm., bearing many groups of telia, which is labelled 

 " Puccinia Xauthii LvS Sal & Beth." 



A very common short-cycle rust still designated by Schweinitz's 

 name. 



*2g28. 24. P. Helenii, L.v.S., rather rare, but prominent, on leaves of 

 Helenium autumnale, Bethlehem. 

 P. spots golden yellow, expanded, sori pulvinate, sparse, and close to 

 each other, convex, at first brown, later beautifully chestnut. 

 Spores rather large, compact. 



Represented by a packet containing the tip of a stem, about 2 

 cm. long, with six small, sessile leaves attached, together with parts 

 of three maturer, lanceolate leaves, the largest 2.5 cm. broad and 7 

 cm. or more long. The packet is labelled " Puccinia Helenii LvS 

 Bethl." An empty duplicate packet is labelled ''2 Puccinia Helenii 

 LvS." 



A careful study of this material leaves little doubt that the host. 

 is Aster salicifolins Lam., and that the rust is the common Puccinia 

 Asteris Duby. The leaves of Helenium have a peculiar lower sur- 

 face due to a sparse pubescence, quite unlike the smooth lower sur- 

 face of the material in the packet, or of Aster salicifolius and of 

 similar lanceolate-leaved species of the genus Aster. From an orig- 

 inal specimen in the Fries Herbarium at Upsala, Lagerheim (Tromso 

 Mns. Aarsh., 17:60, 1894) has given detailed characters as a good 

 species, not remarking any error in the host. Even if the host had 

 been Helenium, yet the rust would undoubtedly have proven to be 

 the same species that occurs on Aster, judging by the description 

 given and the relationship and characteristics of the hosts. 



*2g2g. 25. P. Silphii, L.v.S., sent from Carolina, on leaves of S. trifoliatum, 

 by my friend Denke. 

 P. spots rather small, purple. Sori thick, pulvinate, confluent, aggre- 

 gated, black. Spores compact, concolorous. 



Represented by four small fragments of leaf, the smallest one, 

 1.5 cm. long, bearing a group of telia. The packet is labelled "Puc- 

 cinia Silphii LvS in Sylph trifoliat Denke." 



