FUNGOID PESTS OF CULTIVATED PLANTS. 35 



Carnation Brand. 

 Uromyccs Dianthi (Niessl.), PL II. fig. 37. 



The telcutospores in this parasite are one-celled, in which it differs 

 from Puccinia, although the habit is the same. We met with it in 1891 

 on Carnations imported from Switzerland, and its visits may be repeated. 



At first there are pale spots on the leaves, caused by the innate 

 mycelium ; then scattered minute elevated blisters follow, which are for 

 a long time covered by the cuticle. Finally these pustules crack at the 

 apex and disclose the brown powdery spores. 



The uredospores are spheroid or elliptical, and rather large (40 x 

 17-28 j-i), externally rough, and pale brdwn. No cluster-cups associated 

 with it. 



The teleutospores, which are the last to arrive, are globose, rarely 

 oblong, with the cell membrane thickened at the apex, externally smooth 

 and brown (23-35 x 15-22 ^), a little narrowed below into the long 

 deciduous pedicel. 



Another name by which this brand is sometimes called is Uromyccs 

 czryophyllinus. 



Hitherto its exploits have been chiefly confined to Germany, Italy, 

 Moravia, and the Tyrol, in addition to Switzerland and Britain, but it has 

 appeared at the Cape and in Australia. 



No time should be lost, should the pest make its appearance amongst 

 imported plants, to destroy the bad and spray the doubtful. 



Sacc. Syll. vii. 1949 ; Journ. B.H.S. 1902, p. 652, t. II., f. 13. 



Another species (Uromyces Silenes) is known in Italy, Germany, and 

 Hungary on Silene and DiantJius (Journ. B.H.S. 1902, PI. II., f. 14). 



Carnation Black Mould. 

 Hctcrosporium echinulatum (B. & Br.), PI. II. fig. 39. 



One of the worst enemies of the Carnation. It was first observed in 

 1870, and has occurred very often since. The leaves become studded at 

 first with large round whitish spots, upon which sooty-brown mouldy 

 patches quickly spread, giving a minutely velvety appearance from the 

 tufted threads. These tufts have a habit of arranging themselves in 

 circles, so that the mould has acquired the cognomen of " Fairy Ring of 

 Carnations." 



The threads are very regular, pale olive, and form little tufts or 

 ascicles, each thread being simple or slightly branched, with very short 

 branches, sometimes only like knots or nodules, the upper knots, as well 

 as the apex of the thread, bearing the spores, or conidia. These are 

 cylindrical, with from two to five transverse divisions, mostly two or 

 three, externally rough with minute warts (30-50 x 10-15 /j), slightly 

 coloured. The conidia are capable of germination from each one of the 

 separate cells. 



Numerous minute sclerotia are said to be formed in the dying leaves, 

 which remain as resting spores through the winter. These we have not 

 yet had the opportunity of seeing. 



Known in France, Switzerland, Cape of Good Hope, and Australia. 



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