MucEDmES. 595 



1780. Pexonospoza aienairiae. Berli. " Sandwort Perono- 



spora." 



Fertile threads slender, 6-7 times equally, rarely unequally, 

 dicliotomous ; branches spreading ; ultimate ramuli slender, 

 acute, subulate, nearly erect ; acrospores broadly elliptical, 

 oftentimes very obtuse, small ; membrane scarcely violaceous. — 

 Cooke Micr. F. t. 1 J. 268, 1. 10,/ 211. Pojy. Sc.Mev. iii. t. 8,/. 6. 

 BotrytisarenaricE, Berh. Journ, Hort. Soc. \. p. 31. B. ^ Br. 

 Ann. N.H. no. 623. Fckl.exs.no. 18. De Bary Ann. Sc. Nat. 

 (1863), XX. ^. 13,/. 8, 9. 



On leaves of Arenaria trinervis. June. 



1781. Feronospoxa effusa. Grev. " Spinach Peronospora." 



Fertile threads fasciculate, short, thick, 2-6, rarely 7 times 

 dichotomous above ; acrospores broadly ellipsoid, sometimes 

 very obtuse ; membrane with a violaceous tint. — Cooke Micr. F. 

 «. 10, / 214,215. Rahh. exs. no. 1880. Fckl. exs. no. 11, 12. 

 Botrytis effusa. Grev. Fl. ed.p.4:6S. Eng. Fl. y. p. 343. Desm. 

 Ann. Sc. Nat. (1837), viii. t. 1. Cooke exs. no. 293. Berk. exs. no. 

 53. 



On the under side of leaves of spinach, &c. Spring and 

 autumn. Common. 



Forming effused spots 2-6 lines broad, generally rendering the leaf yellow. 

 Flocci very short, often abruptly recurved. 



1782. Feronospoxa urticae. Casp. " Nettle Peronospora.'"' 



Fertile threads small, loosely 4-6 times dichotomous; branches 

 flexuose, ultimate ramuli subulate, arcuate, often deflexed ; 

 acrospores large, broadly ovoid or subglobose, distinctly pedicel- 

 late ; apices very obtuse ; membrane violaceous. — Cooke Micr. 

 F.p. 216. De Bary Ann. Sc. Nat. (1863), xx. p. 116. Botrytis 

 urticce. B. ^ Br. Ann. N.R.no. d22. Cooke exs. no. 292. 



On leaves of common nettle. 



Patches small, orbicular, greyish lilac; flocci loosely divided above, 

 branches forming an acute angle ; extreme ramuli simple or forked, some- 

 times curved, very rarely inflated. Acrospores large, ovate, apex papillse- 

 form, 



1783. Fexonospoxa txifolioxum. T)eBy. "Clover 



Peronospora." 



Fertile threads cfesjjitose ; equally or unequally 6-7 times 

 chotomous, rarely trichotomous ; ultimate branches subulate, 



2c 2 



