190 



Mycologia 



Upon the basis of the above physiological and morphological 

 differences, the aecial form of Coleosporium elephant opodis 

 (Schw.) Thiim. is designated Peridermium elephantopodis 

 (Schw.) Hedge, and Hahn, comb. nov. to distinguish it from 

 other species of the form genus 'Peridermium, with the following 

 description : 



Pyenia amphigenous, solitary to several in one or two rows on 

 chlorotic spots more commonly on the inner sides of the needles, 

 dehiscent by a longitudinal slit, capucine-buff to orange-buff when 

 immature, cadmium-orange to orange when sporulating, amber- 

 brown to antique-brown at the time aecia are formed, 0.35-0.64 

 mm. wide, 0.36-1.06 mm. long, 0.08-0.2 mm. high, averaging 0.42 

 by 0.75 by 0.12 mm. ; pyenospores, ovoid to ellipsoid 2-4 by 4-6 fx, 

 averaging 2.3 by 4.1 fi. 



Aecia amphigenous, solitary to few in one or two short rows, 

 more commonly on the inner sides of the needles, flattened later- 

 ally, irregularly triangular to rectangular in side view, 0.3-0.9 

 mm. wide, 1. 1-7.9 mm. long, 1.0-3.6 mm. high, averaging 0.7 by 

 3.5, by 2.3 mm. ; peridia often vertically striated, orange-pink 

 when fresh, rupturing longitudinally at the apex with irregularly 

 notched edges ; peridial cells in one layer, slightly or not over- 

 lapping, rectangular in cross section 20-40 by 32-72 fx, averaging 

 32 by 47 fx, with thick walls, 6-12 fx in diameter, averaging 8.5^, 

 walls commonly verrucose, the inner with thickly set papillae 

 1 — 2 [x in diameter, 3-6 /x long, averaging 1.5 by 4.3^, aeeiospores 

 globoid to obovoid, or ellipsoid,, capucine-orange in mass 14-24 by 

 20-32 ll, averaging 19 by 26 ft, with walls slightly or not at all 

 thickened at the apex, 3-6 fx thick, averaging 4.2 /x, the outer 

 surface closely verrucose with tubercles 1-2 /x in diameter, 2-4 fx 

 long, averaging 1.4 'by 2.6 ft. 



The foregoing description is based on aecia from Pinus cari- 

 baea (20818) grown under controlled conditions in the green- 

 house at Washington, D. C, from inoculations with sporidia from 

 the telia of Coleosporium elephamt opodis from Elephantopus 

 carolinianus. 



Coleosporium elephantopodis (Schw.) Thiim. has been found 

 in the United States as follows, the data being taken from col- 

 lections made by members of this office, chiefly by the senior 

 writer. 



O and I. On Pinus: 



