91 
The three forms of conidia were found associated with Colleto- 
trichum gloeosporioules on the pale brown withered portion of leaf, 
but on the scabby portion only (a) and ( b ) were met with. 
This fungus, which is probably only the conidial phase of some 
higher form, occurs generally on the surface of the scab as a 
streaky discolouration, and consists of a more or less continuous 
layer of colourless or yellowish-green hyphce bearing similarly 
coloured conidia of the Monilia and Cladosporium- type. On the 
withered tip of the leaf, free from the scabs, there was found in 
addition a Sporodesmhini-ty\w of conidiuin, associated with the 
CoUetoirichum and Sphaerella. 
While the primary cause of the scab-like bodies may have been 
the Scarlet Mite observed by Mr. Tryon, they were afterwards 
invaded by this fungus, which also caused the decay towards the 
tip. (Figs. 62, 63, 64, 65.) 
34. CITRUS CONIOTHECIUM. 
(Coniothecium citri , n. sp.) 
Forming numerous, minute, brownish patches, with raised brown 
or black margins, on upper surface of leaf, often confluent and 
ultimately producing irregular ruptures. 
Tufts very small, black, often effused. 
Hypbse very scanty, short, creeping, up to Ip. broad. 
Conidia smoky yellowish-brown, semi-pellucid, in irregular 
clusters, cruciately divided, somewhat oblong, average, 19-20/z. 
On Orange-leaf. March, 1899. Wangaratta, Victoria. 
This species is quite different in habit from that found on the 
fruit of the Shaddock. C.scabi'um (McAlp.) forms black effused 
patches resembling “ Sooty Mould,” while this one occurs on 
definite spots circumscribed by regular raised margins. It is 
undoubtedly the cause of the rupturing and ultimate decay of the 
leaf, so that although this genus is badly defined and many of the 
species are doubtful, still it produces definite effects, and, from 
the point of view of Vegetable Pathology, is quite as distinct as 
any other species. (Figs. 66, 67.) 
35. CITRUS MACROSPORIUM. 
(Macrosporium citri , n. sp.) 
Forming densely gregarious, numerous, minute, dingy-green 
tufts, particularly along veins and covering otherwise diseased 
spots, mostly on under surface of leaves. 
Ilyphce fasciculate, ascending, septate, not constricted at septa, 
occasionally sparingly branched, olivaceous or pale green, 5-7^/z. 
broad and sometimes 137//- long. Conidia variable in form and 
