373 



host. Since its exact affinities are at present unknown it is best for 

 the present referred to as above/ 



127. Aecidium Ivae sp. nov. 



0. Pycnia amphigenous, crowded in yellowish spots, 3-15 mm. in 

 diameter, noticeable, subepidermal, light yellow to light chestnut-brown, 

 punctiform, 80-160 by 95-160;ji, ostiolar filaments up to 80;j. long. 



1. Aecia usually hypophyllous, sometimes amphigenous, crowded on 

 spots with the pycnia, cupulate, 0.2-0.4 mm. in diameter; peridium 

 brownish yellow, recurved, erose; peridial cells rhomboidal in longitudial 

 section, 19-27 by 35-51sj., overlapping, wall 5-7^^ thick, outer wall smooth, 

 transversely striate, inner wall closely and coarsely verrucose; aecio- 

 spores globoid or ellipsoid 21-29 by 26-23[j.; wall colorless or pale yellow, 

 2-3;j. thick, finely and closely verrucose. 



On Ambrosiaceae : 



Iva ovaria Bartlett (/. friitescens A. Gray not L.) , Lewes, 

 Aug. 14, 1907, (1676). 

 This species is evidently a heteroecious fo:-m and occurs otherwise, 

 so far as is known, in salt marshes along the Atlantic coast and Gulf 

 of Mexico in Virginia, Florida and Louisiana. It differs from Aecidium 

 intermixtum Pk. (Puccinia intermixta Pk.) in the larger aeciospores 

 and in the fact that the aecia develop from a limited mycelium. 



128. Aecidium Uvulariae Schw. Nat. Ges. Leipzig 1:69. 1822. 

 On Convallariaceae : 



Uvularia sessifolia L., Seaford, .June 4, 1908, (2059) ; Cooch's 

 Bridge, May 25, 1915, C. O. Houghton. 

 The above Aecidium is scarcely distinguishable from Aecidium 

 Majanthae Schum. which has been shown by European investigators 

 to be connected with uredinia and telia on Phalaris. In America aecidia 

 occurring on Salamonia, Unifolium and Vagnera have been similarly 

 referred to P. Majanthae (Schw.) Arth. (P. sessilis Schw.) though no 

 successful cultures have been made. Since slight morphological differ- 



^ Since the above was written cultures conducted in this laboratory and reported by 

 Arthur (Mycol. 9 :.307. 1917) show that aecia on Rudheckia laciniata are genetically con- 

 nected with uredinia and telia on Carex referred to Uromyces perigynius (cf. 114). He 

 obtained successful infection resulting in aecia on R. laciniata following exposure to 

 germinating telia on Carex sparganioides. It is therefore probable that the collection 

 listed here from Delaware on R. triloba should be similarly referred. 



