168 FUNGOID PESTS OF CULTIVATED PLANTS. 



attached to each other in chains of from six to ten cells. Whilst remain- 

 ing attached, the ends of the conidia are flattened at the point of junction, 

 but when free they acquire a globose form (10 p diam.), with a thin 

 hyaline membrane, but with granular golden-yellow cell-contents. 



At present this has only been recorded in Britain, and is certainly 

 epiphytal, probably not at all injurious to the plant ; at any rate it is very 

 curious. 



Grevillea, xii. 98 ; Sacc. Syll. vi. p. 633, x. p. 511. 



Two or three kinds of leaf -spot have been caused upon Jasmin-leaves 

 by imperfect fungi, but none of these have been recorded as British. 



PASSION-FLO WEE BLACK MOULD. 

 Zygosporium oscheoides (Mont.), PL XV. fig. 23. 



This minute black mould was first discovered in Cuba, growing on 

 dead leaves, and was only regarded as a saprophyte, but recently it has 

 been recorded on leaves of Passiflora quadrangularis, seemingly under 

 the impression that it was a parasite, and a new species, under the name 

 of Cladotrichum Passiflcra (Pirn.). 



The fertile threads are erect, septate (70 x 3 /j), sooty-brown, inflated 

 and paler at the apex, at the base emitting a semilunar sporophore. 

 Conidia, oval or globose, produced singly or in pairs at the apex of the 

 sporophores (5 p diam. or 12 /* long). 



The peculiarity is that the hyaline conidia are borne at the end of 

 curved club-shaped branches, which is sufficient to identify the species. 



This same mould has been found in Cuba and elsewhere on Screwpines 

 and Palms. 



Gard. Chron. Dec. 5, 1885, p. 724, fig. 164 ; Sacc. Syll. iv. 1591 ; 

 Corda, Icon. vi. 



CACTUS SCAB. 



Diplodia Opuntia (Sacc.). 



The injury caused by this fungus is sometimes severe, the black 

 wart-like outgrowths constituting the sterile portion of the fungus often 

 covering a considerable area, the surrounding tissue becoming discoloured. 

 The mycelium is distinctly localised, and each scale is the outcome of an 

 independent infection. The Diplodia form of fruit is rare but has occurred 

 on Phyllocactus at Isleworth. 



Gard. Chron. Aug. 12, 1905, p. 125, fig. 44. 



STEPHANOTIS LEAF-SPOT. 

 Phyllosticta Stephanotidis (Grove), PI. XV. fig, 24. 



This leaf -spot was detected on the leaves of Stephanotis in 1886, 

 forming round or irregular spots, which are bleached or whitened and 

 surrounded by a thin dark brown line. The receptacles appear on the 

 upper surface, and are small, numerous, and scattered over the spots, 

 nestling beneath the cuticle, which is pierced by the small orifice of the 



