246 



JOUBNAL OF HORTICULTURE AND COTTAGE GARDENEE. 



t October 1, 1868. 



much reduced. The following represent some of the principal 

 types ; 



I.— icroiuM. 



Fig. 1. — A; Spei-mogone containing epermatia (" sperm-ceils "J ; 

 B. " Spores," germ cells produced iu special sheaths (peridia,. 



With this genua are associated three others separated only 

 by slight characters — Eastelia, Peridermiiim, Endopbyllum. 

 Spermogonia freely produced, ultimate destination of the germ- 

 cells unknown ; it has been thought, and may possibly be so, 

 that from them, on the same or other plants, Puccinia-fruits 

 may arise. 



II.— UKEDINEI (Rusts). 



v.— PERONOSPOREI. 





Fig. 2. Credo, spores developed within cells, afterwards free. XLecythe.a, 

 spore8 free, along with them elongated cells (paraphyees). 4. Trichohasis, 

 spores free, often with a short peduncle attached. (Spcrmogones arc 

 hnown to accompany some of the forms). 



Several of these are known to be, and perhaps all may be, 

 conditions of 



III,— PUCCINI.EI. 



6 



Fiff' 5- XenodocJius (gi-ows on Burnet). 6. Aretfma (Rosaceas). 7. Tri- 

 phraciminvi (Meadow Sweet). 8. Puccinla (Grasses). 9. Uromyces 

 (Vetches). 



Sperm-cells rare, but known to occur with pome specie?. 

 Podisoma and Gymnosporangium are associated genera, in 

 which the Puccinia-fruits are imbedded in a tremelloid, gela- 

 tinous mass. 



IV.— USTILAGINEI (Smut and Bunt). 



fl 



Fig 10. frs((7n/7rt (Smnt), sexual conditions nnknowD. n. T illc I ia (Bimi): 

 «, spores, which on germination, b, emit a filament, at the extremity of 

 which short branches arise — these conjugate in pairs (as with Syzyt^ites 

 and some AJgje), after which union a secondary fruit, c, is produced. 



The essential nature of these chaages has yet to be ascer- 

 tained. 



Fig. 12. Cijsfopus : a, " spores," arranged in headed threads, at first 

 suhcutaneous, then esterual through rupture of the plant-integument ; 

 their contents undergo segmentation and afterwards hecomo motile ; 

 fc, sperm-cell; c, germ-cell; a filament is produced from the former, 

 which becomes closely applied to the latter, whilst without investment, 

 after which a strong warted coat is formed. 



Both *' sperm," and 

 tissues of the plant. 



9 



'germ-cells" grow immersed in the 



Fig. 13. Pcrono^pora : a, arborescent threads, external to the surface of the 

 leaf, bear at their tips gemmje, the contents of which, after segmenta- 

 tion, become motile; 6, germ-cell (" oo-spore "), immersed; sperm- 

 cells ? ? 



In this genns, the most deadly in their effects on yegetation 

 of the epiphjllous Fungi are comprised. Suckers, analogous 

 perhaps to the tendiils of higher plants, occur on the mycelium 

 of members both of this and the former genus. 



VI.— EEYSIPHEI. 



Fig. 14. Enisiplic : mycelium creeping over the external surface of 

 the leaf, and throwing up at intervals jointed threads, a, the contents 

 of the joints after segmentation become motile gemma? ; b, fruit borne 

 externally, globular and horny in texture, containing within them 

 asci (c) or '* spore-sacs " ; d, spores ; e, appendages. 



The immature conditions of Fungi in this order constitute 

 the spurious genus Oidium, so well known in connection with 

 the Yiue disease. Sexual conditions obscure. 



With regard to the Fungi found parasitic in diseases of the 



human skin, so much of their life history yet remains to be 



discovered that speculation on their affinities cannot at the 



' present time be other than barren of result. The well-known 



