FUNGOID PESTS OF CULTIVATED PLANTS. 165 



CAMELLIA SCAB. 

 Goryneum Camellia (Mass.). 



It must be confessed that some little mystery surrounds this parasite, 

 which has only been detected once upon living Camellia leaves. The large 

 blotched spots exactly resemble those which are caused in the Camellia 

 blotch, but in that species the conidia are crowned at the apex with three 

 or four long and spreading hairs, whilst in the present species the spores 

 are similar in form and size, but without any crest of hairs. This may 

 seem to be but a slight distinction, but it is the principal difference 

 between Pestalozzia and Coryneum. It may be possible that this is an 

 abnormal form of Pestalozzia Guepini in which the hairs are suppressed. 



The pustules are numerous on the whitened spots, splitting the cuticle 

 in a linear, triangular, or stellate manner, so as to allow of the escape of 

 the conidia. The latter are lanceolate (30xlO/j), with from two to four 

 coloured cells in the middle, and a small triangular uncoloured apical and 

 basal cell, supported at first on slender pedicels of the same length as 

 the conidia. 



The same remarks as to prevention apply as in the case of Pestalozzia, 

 if this is not really, as we suspect, the same species. 



Grevillea, xx. p. 8 (1891). 



CAMELLIA BLACK MOULD. 

 c Macrosporium Camellia (C. & M.), PI. XIV. fig. 15. 



Externally, and to the naked eye, this form of spotting the living 

 leaves of Camellia so much resembles that caused by Pestalozzia Guepini 

 that even an experienced eye can scarcely detect the difference until the 

 microscope is employed. The silvery- white spots on the upper surface 

 are of the same size, usually half an inch, and there is a distinct brown 

 margin. 



The scattered dark points are small, but when magnified are found to 

 consist of tufts of brown or pale olive threads piercing the cuticle. The 

 threads are flexuous (30-40 yu long), with cross divisions.- Mixed with 

 these, or supported upon them, are the club-shaped conidia, with, at 

 first, three cross divisions, but at length double that number, with longi- 

 tudinal divisions, like a brick wall (50-60 x 15-25 p). Downwards these 

 conidia are attenuated into the pale olive pedicel, the whole upper part of 

 .the conidium being of a little darker olive. 



This may not be an injurious pest, as many of the species are sapro- 

 phytic, and the possibility would suggest itself, whether this mould has 

 not taken possession of a dead spot, caused by the Pestalozzia, and 

 become established upon it. At any rate, conidia of Pestalozzia were 

 sought diligently, and not a single one could be found. 



Grevillea, xvii. 42 ; Sacc. Syll. x. 7837. 



GARDENIA CANKEK. 

 PL XIV. fig. 16. 



Tumours are formed on the stems, at the base, just above the ground, 

 or on branches near a fork, on Gardenia and also on Camellia. They 



