FUNGUS PESTS OF THE CAENATION FA]\ULY. 



651 



are to be found in the dying leaves. These sclerotia rest during the 

 winter, and in the ensuing spring produce small conidia, which, on 

 coming in contact with living leaves, will produce the mould. It must 

 be borne in mind also that each cell of the mature normal conidia will 

 germinate and produce a small secondary spore. The inference is 

 that this is a dangerous parasite, because so persistent in the reproduc- 

 tion and continuation of the species that the destruction of all parts of 

 diseased plants becomes imperative. The other black mould, Macro- 

 sporium nohile, is comparatively rare on Carnation leaves in the West of 

 England (fig. 8). The large compound muriform conidia germinate from 

 every one of its numerous cells. 



The smuts, or Ustilacjincs, are known well enough on grasses and 

 cereals, but are less obtrusive and less common on garden plants. The 

 anther smut, Ustilago violacca, attacks the anthers of Silene, Lychnis, 

 Sec, giving the flowers the appearance of being dusted with soot (fig. 11), 

 It is generally distributed throughout Europe, and reaches to the United 

 States. The spores of this fungus are small and globose, becoming free, 

 and not collected in clusters. 



There are other smuts in which the spores are paler in colour, and 

 collected in clusters or glomerules, more or less firmly attached to each 

 other. One of these is called Urocystis purimrca, hitherto found only 

 in the ovaries of Diantlius in Hungary, and consequently very little 

 known. Another is Sorosporium Saponarice, found on the floral organs 

 of Saponaria, Diantlius, Stellaria, and Lychnis, in Britain, France, 

 Germany, Austria, Italy, and Algeria. The glomerules consist of a great 

 number of normally globose or elliptical spores (fig. 9), which become 

 angular by compression, of an ochrey colour, with the external surface 

 rough or warted. When quite mature these spores separate, and each 

 germinates on its own account. Another species has been described 

 under the name of Sorosporiuni Dianthi, said to occur on Dianthus 

 prolifer in Italy, but possibly it is the same species as the foregoing, as 

 it presents no distinctive characters. These, so far as I am aware, are 

 the only smuts which have been recorded for the Carnation family, and 

 in all cases are developed in the flowers, and do not afi'ect the foliage. 



We now arrive at the group of Fungus Pests w^hich are kno'^n to 

 cultivators as cluster-cups, rusts, and brands, but to science as Uredims. 

 For all practical purposes it seems better to treat all the forms as they 

 appear to the eye, and as in former times they were regarded by 

 botanists, as distinct entities or species. The cultivator desires to 

 recognise them and give them their names, without troubling himself as 

 to their genetic relations, or only collaterally so. To him the cluster- 

 cup appeals as a cluster-cup, and not as a form or condition of a rust, or 

 a brand, a Urcdo or a Puccinia. Whether this course is scientifically 

 accurate W' e do not stay to inquire, so long as we are convinced that it is 

 the most convenient, and is used in a popular sense, without prejudice 

 to any real or imaginary life-histories. Take an extreme case — the 

 cultivator will be more satisfied to call the cluster-cups of the Barberry 

 by its old name of ^cidium Berber idis, rather than jpcidiospores of 

 Puccinia graminis, supposing even that he accepts their genetic relation- 

 ship. 



