196 FUNGOID PESTS OF CULTIVATED PLANTS. 



The spots are whitish, and at one time or other circled with red. Pustules 

 minute, seated on the spots. Sporules small, elliptical. 



This is another of the species which appears to have heen hurriedly 

 described from a Bingle set of specimens, and has not heen seen again. 



Berk.d Br. Ann. X. H. No. 1897; Grevilha, x. 1881, p. 49; Sacc. 

 Syll. iii. 8686. 



Parasites do not appear hitherto to have caused much trouble with 

 Coin tea arborcscens, notwithstanding its extensive cultivation, so that we 

 have no record of any British species. 



Mountain Ash Cluster-cups. 

 Rccstclia cornuta (Gmel.), PI. XVIII. fig. 40. 



Under the name of Gymnosporcmgvum j uniperinum, the presumed 

 teleutospores which succeed these cluster-cups on twigs of Juniper, the 

 original name is concealed. Our parasite, or at any rate that part of it 

 which concerns us, makes its appearance on the leaves of the Mountain 

 Ash and Amelanchier. They are seated in tufts upon yellow spots, on 

 the upper surface. The cups are long horn-like tubes (up to 8 mm. long), 

 which are curved, and whitish at first, then yellowish or reddish, with a 

 toothed margin. The rccidiospores are spherical, then compressed and 

 angular, of a brownish-yellow colour (20-28 x 16-21 fi), delicately warted 

 on the surface. 



The pest is known in Britain, Belgium, Germany, Finland, Switzerland, 

 Italy, Austria, and North America. 



San: Syll. vii. 2607 ; Cooke, M. F. f. 18, 19 ; Cooke, Ildbk. No. 1598, 

 f. 218 . i'un. t. 319. 



Sumach Leaf-spots. 



Leaf-spots are numerous, and common, on various species of Rhus in 

 North America, but we have no record of their occurrence in Britain. 

 There are not less than fifteen species of leaf parasites that are known and 

 described, but probably not five of them are European. 



GYMNOSPEKMS. 

 Savin Jelly-bust. 

 tmno8porangvum Sabince (Dicks), PI. XVIII. fig. 41. 



According to theory, the proper cluster-cups of this pest are produced 

 upon the leaves, twigs, and fruits of the Pear tree, audit was formerly known 



TlttsteUa cancellata. The teleutospores arc exuded in a gelatinous 

 mass from the branches of Jumpertu Sabina. We deal with the cluster- 

 ou] of the Pear tr< e. 



The ti leu: ity swellings in the branches of the host- 



plant, and at length break through in irregular conical or cylindrical, 

 obti slatinoua, orange-coloured masses, sometimes compressed, and 



sometimes divided ( 10 mm. long) like little flabby tongues. This gela- 

 tinous mass consists of teleuto pores with their stems adhering together 



