

'" ¥ 

 II 



.1 



Mi 





- 



22 



In Eiudiio three spoeies are doscriliod a? follows; 



I*. O.vijaninthu', (DC.) DHy. — Apiiciiihijivji S or iiioi'e, aliout e(iiial 

 to the (liaiii(>ter ol' tlio pcritliecinni, staiidiiiji' erect on its upitei' surl'ace. 

 On Crata'(/iii<, Sorhiifi and Jfesji/'/tis. 



I*, tridavtyhi, (Wallr.) J)J>y. — Appendaj^os 3-7, standing erect in 

 a parallel Imndle on tln' summit ol" the perithceium. On Prnnvs sps. 



P. myi'tilliHO, (Si'hnliert) Kunze. — Ajipenda.ues G-10, arising 

 Irom the ujtjier siniaee of the jieritlieeium, Imt radiating divergently 

 or rcllexed. On Vacrinhim. 



European s])eeimens on the al)ove hosts show these distinguishing 

 characters snilieiently well, but American specimens on Primus can- 

 not l>c sejiaiated irom those on Cratrrf/tiK, etc. Tlieic ajjjiear to be 

 none on Vacv'niiuin. Whatever may lie done with European I'ornis, 

 the American ones must be considered one sjiecies. 



P. biiiiu'iuhtii, C. & P. Erysiphei of the V. S. Journ. Bot. 1872. 

 Pk. 25th Kep. ].. i)4. 



Aniphigenous. Mycelium thin, arachnoid, rather persistent. 

 Perithccia small, 70-90 /i, scattered; a]ij)endages 0-12. 3-5 times as 

 long as the diameter of the perithceium, hyaline, with a conspicuous, 

 widely spreading fork at the apex, each branch of whicii is sometimes 

 divided. A sens glol)ose. Sjioridia mostly 18-21 /i long. 



On Ifdunimdis VtryiniuiK/, Massachusetts (Seymour), New York 

 (Peck), Illinois (Waite). 



An easily recoginzed species, by the nni(|ue character of the tips 

 of tlie appendages, which ai)i>ruach. though they arc easily ditVerent 

 from those oi Unrrmthi Accr/'s. The mycelium shows much more on 

 the upper suiface of the leaves, but is also conniion below. 



MICROSPH.ERA, Lev. 



Aim. Sci. N.-it. Ser. Ill, Tome XV, p. 3S1. 



Perithceium containing several asci. Ajipendages free from the 

 mycelium, more or less dichotomously branched at the end. 



M. Meiiispeniii, Howe, liull. Torr. IJot. Club, V, p. 3. 



Epi])hyllous. Mycelium rather abundant, thin and wid.ely eflused, 

 l)ut thickened in certain circular spots, of which there are usually not 

 more than three or lour on a leaf. I'erithecia aggregated upon the 

 special denser s})ots of the mycelium, otherwise remotely scattered, 

 black, very variable in size, (50-115 /i diani; ajipendages not numer- 

 ous, 8-15, rather rigid, tinted at base, exceedingly vaiiable in length 

 and amount of branching, 1-7 times diameter of jierithecium in length 

 and 1-7 times dichotomouslv branched, the l)ranches of the first 



