3? 



Journal of Mycology [Vol. 10 



L. and S. caesia L., clearly in accordance with the vigor of the 

 host plants, while a sowing on S. rigida L. wholly failed, the 

 host showing a weak growth. 



The above sowings were all made from material on Carex 

 varia. The collection on C. lanuginosa, taken at the same time 

 and place, appearing in every way to be the same species, and 

 to be in equally viable condition, was sown under equally favor- 

 able circumtsances on Silpliiuni perfoliatum, Ribes Cynosbati, 

 five species of Aster, and on Solidago rigida, S. serotina and re- 

 peatedly on 5*. Canadensis, all with no infection. 



Whether the failure to infect the Solidago was due to some 

 undetected oversight in manipulation, or is an indication of spe- 

 cific or racial difference in the rust, is a matter for which the 

 facts do not warrant an opinion. 



It is not easy to determine if this rust has been previously 

 described and named or not. Upon morphological grounds it 

 is clearly distinct from Uromyces caricina E. & E. and U. tninu- 

 tns Diet., hut it may he the same as U. perigynius Halst. It also 

 agrees well with collections from Wisconsin 13 on Carex gracillima 

 Schw., from Decorah. Iowa, 14 on C. pubescens Muhl., and from 

 ( ireencastle. Ind.,'" on what was taken to be C. pubescens, hut 

 which a re- examination shows to be almost certainly C. virescens 

 Muhl. If the rust on ( '. varia and C. lanuginosa had shown the 

 same cultural behavior, I would have been inclined to unite these 

 several collections undei one name. But realizing the need of 

 advancing cautiously among a group of species where only the 

 first step has been taken, it seems wiser to give a separate name 

 to the form about which, we have definite knowledge, and leave 

 the others to be dealt with later. The rust on C. varia with its 

 alternate form is therefore, characterized under a new name, as 

 follows: 



Uromyces Solidagint-Caricis nom. nov. 



(). Spermogonia epiphyllous, in small groups on yellow spots, punc- 

 tiform, honey yellow, subepidermal, in. vertical section shown to be 

 globose, about 115 ;i in diameter ; isticlar filaments free, 60 ft long. 



I. Aecidia hypophyllous. in groups, often circinating. peridia pale, 

 low cylindrical, margin revolute, lacerate; aecidiospores globoid, or 

 slightly elongated. 13-16 by 14-18 fi\ wall colorless, thin, 1 <j. or some- 

 times a little more, minutely rugose. 



II. Uredosori not seen ; uredospores among the teleutospores oval 

 or obovate, about 16 by 23 // ; wall thin, echinulate. 



III. Teleutosori hypophyllous, round, oblong or sometimes elong- 

 ated, pulvinate, early naked, firm, chestnut-brown: teleutospores obovate, 

 15-18 by 23-28 //. . rounded or obtuse above, narrowed below; wall smooth, 

 thin, 1.5-2//, apex greatly thickened, 6-10//; pedicel slender, tinted, as 

 long as the spore, or longer. 



13 Trans. Wis. Acad. Sci. 9:180. 1892. Same 74:90. 1903. 

 14 Bot. Gaz. 16:226. 1891. 

 15 Same, 1. c. 



