North American Species of Puccinia on Carex 213 



responsible for the original culture. There are other cases where 

 morphological correspondence between aeciospores and uredinio- 

 spores has led to successful connections (see Arthur, Bot. Gaz. 

 29:274-275, 1900). Such cases tend to indicate a possible ho- 

 mology between these spore forms. 



4. Puccinia spatiosa sp. nov. 

 O & I. Pycnia and aecia unknown. 



II. Urediniospores broadly ellipsoid, 26-29 X 30-39 ; wall 

 light cinnamon-brown, 2-2.5 /* thick, sparsely and conspicuously 

 echinulate, the pores 3, or sometimes 4, approximately equatorial. 



III. Telia oval oblong or linear, 0.5-1 mm. long, blackish ; 

 teliospores narrowly obovoid, 24-29 X 45-64 /x, considerably con- 

 stricted at the septum, rounded above, rounded or narrowed be- 

 low ; wall chestnut-brown, 1.5-2^ thick, very much thicker above, 

 16-23//,; pedicel nearly colorless, once to once and a half length 

 of spore. 



On Carex sp. 



Type collected at Brookings, S. D., March 21, 1908, A. G. 

 Johnson. 



So far as pore characters are concerned the form here described 

 agrees with a group of species, of which the forms having aecia 

 on Urtica and Ribes are prominent members, but it differs from 

 all of these in having more robust especially broader spores, both 

 uredinio- and teliospores. As compared with the usual oblong- 

 clavate teliospores of the sedge rusts these are broad enough and 

 rounded above so as to give an obovoid effect. 



5. Puccinia minuta Dietel; Atkinson, Bull. Cornell Univ. 3: 19, 



1897 



Puccinia riparia Holway, Jour. Myc. 10:163, in part. 1904. 

 O & I. Pycnia and aecia unknown. 



II. Urediniospores broadly ellipsoid or obovoid, 19-26 X 26- 

 39 /x; wall cinnamon-brown, about 1.5 thick, evenly and rather 

 sparsely echinulate, the pores 3, approximately equatorial. 



III. Teliospores clavate-oblong or cuneate, small, 13-23 X 

 26-42 /x, rounded or truncate above, not or only slightly constricted 

 at the septum; wall light chestnut-brown, 1-1.5^ thick, much 

 thicker at apex, 5-10 /a; pedicel slightly tinted, about one-half 

 length of spore. 



