438 Rev. M. J. Berkeley on British Fungi. 



at the base, attenuated above. Sporidia forming subglobose 

 heads attached by very short peduncles, oblongo- elliptic, tri- 

 septate. 



A most elegant species, to which the figure does not do 

 justice. It is white in every stage of growth, by which it is 

 distinguished, and by the large heads of distinctly septate 

 sporidia. 



Tab. XIV. fig. 27. a, Dactylium sph&rocephalum, nat. size ; b, tuft of 

 ditto, magnified ; c, a sporidium highly magnified. 



*244. Oidium leucoconium, Desm. ! Fr. Syst. Myc. vol. iii. 

 p. 432. This species, O. erysiphoides and O. monilioides, are, 

 I have no doubt, the early stages of various species of Erysiphe. 



245. Fusisporium udum,n. s. Late effusum, tremellinum; 

 sordide aurantiacum ; floccis hyphasmatis decumbentibus, 

 parce ramosis ; sporidiis longis, curvulis, 3 — 5 septatis, utrin- 

 que acutis. On trees in spring. King's ClifFe. 



Forming a broad tremelloid mass wet with the overflowing 

 sap, composed of slightly branched decumbent filaments, some 

 of which are closely septate, others contain a series of globose 

 nuclei, while others are quite simple. Sporidia 3 — 5 septate 

 elongated curved, acute at either end, the contents of the ar- 

 ticulations orange. In age the septa are absorbed, and there 

 is a row of irregular nuclei. 



Tab. XIV. fig. 28. a, flocci and sporidia, magnified ; b, sporidia, highly 

 magnified. 



246. F. Beta, Desm. ! exs. n. 305. Ann. d. Sc. Nat. vol. xix. 

 tab. 18. On beet root. Apethorpe. 



247. F. GeorgincB, Kl. ! exs. n. 186. On roots of dahlia. 

 Apethorpe. 



248. F. album, Desm. ! n. 929. On dry but green leaves 

 of the oak. Milton, Norths. Moug. and Nest. n. 894. is this 

 species, and not the true F. griseum of Greville. 



249. Fusarium lateritium, Nees, Fr. Syst. Myc, vol. iii. p. 

 4/0. On Sophora Japonica. Milton. Mr. Henderson. On 

 willow, King's ClifTe. On lime, Burleigh, Norths. 



*250.. Melanconium bicolor, Nees, Fr. Syst. Myc. vol. iii. 

 p. 488. Didymosporium elevatum is certainly only a form of 

 this species. In Fries's specimens in Scler. Suec. the sporidia 

 are not didymous, neither are they in Dr. Greville's plant. 

 More modern microscopes show clearly that the supposed 

 septum arose from an optical deception caused by the presence 

 of the nucleus. The plant again of Carmichael, referred to 

 M. sphceroideum, Lk., is a form of the same species. 



251. M. sphcerospermum, Lk., Fr. Syst. Myc. vol. iii. p. 489. 



