NEW SPECIES OF PERIDERMIUM 



Geo. G. Hedgcock and N. Rex Hunt 



A description is given in this paper of five new species of 

 foliicolons Peridermium on pine in the eastern United States. 

 The first three species have been proven by the writers by inocu- 

 lations with the aeciospores under controlled conditions in green- 

 houses to be the aecial forms of species of Coleosporium. These 

 are described and named to distinguish them from other species 

 of the form genus Peridermium on pine needles. Types of these 

 species have been deposited in the pathological collections of the 

 Department of Agriculture at Washington, D. C. 



I. Peridermium ipomoeae sp. nov., the aecial form of Coleo- 

 sporium ipomoeae (Schw.) Burrill 



Pycnia amphigenous, scattered or frequently numerous and 

 arranged in rows, usually on the same side with or opposite to 

 the aecia on light or yellow green 1 spots in the needles, olivaceous 

 black, o.i i to 0.36 mm. broad by 0.28 to 0.64 mm. long, averag- 

 ing 0.24 by 0.41 mm. 



Aecia flattened laterally, scattered, usually in a single row, 0.24 

 to 0.56 mm. high by 0.88 to 2.32 mm. long, averaging 0.4 by 1.6 

 mm. ; peridial cells ovoid to elliptic or rhomboid in face view, 

 mostly overlapping, 16 to 26 by 18 to 47 fi, averaging 21 by 41 /x, 

 with walls 2 to 5 /x thick, the inner closely and finely verrucose ; 

 aeciospores ovoid to ellipsoid, 16 to 20 by 22 to 27 /x, averaging 

 18 by 25 fx, walls colorless and verrucose with somewhat deciduous 

 tubercles 1 to 2 /x in diameter and 1 to 3 xt high. 



Peridermium ipomoeae has been collected on the needles of the 

 following species of pine : 



On Pinus echinata Mill, in Alabama, Arkansas, Georgia, North 

 Carolina, South Carolina, Texas, and Virginia. 



On Pinus palustris Mill, in Florida and South Carolina. 



1 Colors used are those given in Color Standards and Nomenclature by 

 Robert Ridgway, Washington, D. C, 1912. 



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