236 MICROSCOPIC FUNGI. 



Peronospora Hyoscyami, De By. Henbane Mould; 

 fertile threads thick, 5-3 times dichotomous, branches patent, 

 attenuated, straight or slightly curveJ, the ultimate forming a 

 very obtuse angle, divergent, short, subulate, straight, acute ; 

 conidia small, ellipsoid, very obtuse; epispore pale violaceous. — 

 On common Henbane. Market Deeping. 



Peronospora entospora,B. and Br. Fleabane Mould \ 



fertile threads simple, clavate, surmounted by a crown of apiculi 

 bearing the ellipsoidal conidia, each of which is papillate at the 

 apex, endochrome granular; oogonia yellowish, subglobose, 

 tuberculide. — On Erigeron Canadense. 



Peronospora Trifoliorurn, De By. Clover Mould; 

 fertile threads ctespitose, equally or unequally 6-7 times dicho- 

 tomous, rarely trichotomous ; ultimate branches subulate, acute, 

 slightly curved ; acrospores ellipsoid, very obtuse ; membrane 

 with a slightly violaceous tint ; oospores large ; epispore brown. — 

 On Lucern (Medicago saliva). Highgate and Hampstead, 1864. 



Peronospora grisea, Ung. Veronica Mould; fertile 

 threads erect, fasciculate, grey, 5-7 times regularly dichoto- 

 mous ; branches gradually attenuated ; primary oblique, erect, 

 others spreading, ilexuose; ultimate mostly unequal, slightly 

 arcuate; acrospores ellipsoid or ovoid, obtuse; membrane pale 

 and dirty violet. — On leaves of Veronica beccahunga. Mav, 1846. 

 (Plate X. fig. 213.) 



Peronospora ealotheea, De Buy. Flocci slender, 7-9 

 times dichotomous ; primary branches oblique, erect, the rest, 

 patent, squarrose, slender; ultimate ramuli short, straight, or 

 curved; acrospores elliptical; oospores globose; epispore bay- 

 brown, minutely reticulated. — On Galium Aparine. 



Peronospora arborescens, Betk. Poppy Mould; fer- 

 tile threads slender, erect, 7-10 times dichotomous above; 

 branches more or less flexuose, squarrose, spreading, gradually 

 attenuated ; ultimate ramuli shortly subulate, more or less arcuate; 

 acrospores very small, subglobose ; membrane scarcely violaceous. 

 — On the Corn Poppy. June. Common. 



Peronospora Schleidciiiana, De By. (P. destructor, B.) 

 Onion Mould; fertile thieads robust, erect, not septate, 

 branched alternately; ultimate ramuli forked and uncinate or 

 divaricate ; acrospores seated on the tips of the ultimate ramuli, 

 obovoid or nearly pear-shaped, attenuated at the base; mem- 

 brane of a dirty violet-colour.— On the leaves of various species 

 of Allium. Often plentiful. (Plate XIII. fig. 263.) 



