=Coleosporium Rhinanthacearum=, Lév. COW-WHEAT RUST; spots none or subferruginous; sori irregular, confluent, on the under, rarely on both surfaces; spores subglobose, compact, golden-yellow.—On _Euphrasia officinalis_, _Bartsia odontites_, _Melampyrum arvense_, &c. August and September. Common. (Plate VIII. figs. 170, 177.) MELAMPSORA, _Cast_. Spores of two orders, crowded into a dense compact mass, with or without a covering, wedge-shaped. _Berk. Outl._, p. 333. =Melampsora Euphorbiæ=, Cast. Hypophyllous; sori of summer spores golden-yellow, scattered, distinct, sometimes cauline; spores small, subglobose; sori of perfect spores becoming black, small, roundish, spores prismatic, membrane thickened above, dark brown.—On leaves and stems of _Euphorbia helioscopia_, _E. exigua_, and other species of spurge. Common. (Plate IX. figs. 193, 194.) =Melampsora Populina=, Lév. Hypophyllous, epiphyllous, or amphigenous, at first yellow or orange; summer spores obovate-oblong, attenuated or truncate, echinulate; paraphyses obovate, capitate or claviform, abundant in fully-ripened sori; sori of perfect spores at first tawny yellow, becoming black during the winter, swelling in the spring, and becoming of a cinnamon-colour, hypophyllous, roundish, or oblong; spores prism-shaped, 5-6 together, yellowish, smooth.—On leaves of _Populus nigra_. Common. Spores perfected in February. (Plate IX. figs. 195, 196.) =Melampsora Tremulæ=, Tul. Hypophyllous; sori of summer spores punctiform, prominent, or papillæform, numerous; spores tawny-yellow, elliptical or obovate; paraphyses slender; sori of perfect spores scattered, at length blackish; spores elongated, compressed, attenuated downwards, yellowish.—On leaves of _Populus tremula_. Common. Spores perfected during the winter. =Melampsora Betulina=, Desm. Hypophyllous; sori of summer spores bright yellow or orange, oblong, cylindrical, or obovate, truncate at the base, echinulate; paraphyses encircling or intermixed, obovate, smooth, hyaline; sori of perfect spores confluent, of an obscure brown in the winter, becoming of a bright orange when mature; spores elongated, attenuated below, polygonal, ochraceous.—On leaves of _Betula alba_. Common. Spores perfected in January and February. (Plate IX. figs. 189, 190.) =Melampsora Salicina=, Lév. Epiphyllous or hypophyllous; sori, or heaps of summer spores, scattered, pale orange, bright orange, or cinereous; spores ovato-globose, paraphyses capitate, rarely obovate; sori of perfect spores epiphyllous, scattered or aggregate, at first yellowish-tawny, then brownish, at length nearly black, bullate; spores oblong, closely packed, and laterally compressed.—On _Salix viminalis_ and _S. capræa_. Common. Spores perfected in February. (Plate IX. figs. 191, 192.) CYSTOPUS.