PAPKRS r.IVIXG RUSTS OF NORTH AMERICA. 251 



RcprcsciUctl liy an orij^iiial packet, containinj,' |)art of one leaf 

 about 3 Ijy 6 cm., bearing many groiij)s of tclia, which is labelled 

 " Puccinia Xantliii LvS Sal & Beth." 



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

 name. 



*2928. 24. P. Hcloiiii, L.V.S., rather rare, l)ut prominent, on leaves of 

 Ilclciiiiim autumnalc, Bethleliem. 

 P. spots golden yellow, e.xpandecl, 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 Hclenii LvS 

 Bethl." An empty duplicate packet is labelled "2 Puccinia Helcnii 

 LvS." 



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

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

 Astcris Duby. The leaves of HcJciiiiuii 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 salicifoliiis and of 

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

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

 Miis. AarsJi., 17:60, 1894) has given detailed characters as a good 

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

 been Hclcniiim, 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 mj' 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." 



