127 
Ascigerous Stage of a ‘ Brown Rot ’ Fungus . 
and Ruhland for Sclerotinia cinerea are too low for the American Sclero- 
tinia. Again, Aderhold and Ruhland quote the size of the conidia as the 
chief distinguishing character of the Monilia forms of S.laxa and S. cinerea. 
They find the average size of the conidia of .S'. laxa to be i6*i x to- 8 [i and 
that of cinerea 13-8 x 9-95 ju; the former, however, is approximately the 
average size of the summer conidia of Monilia cinerea , Bon., the latter 
rather higher than that of the winter conidia of the same fungus. 
In order to throw further light on the relationship of these forms, 
attempts have been made by the writer to induce the development of 
apothecia by exposing mummied fruit on the ground and in pots of soil in 
the open. These attempts at first met with no success, as the ‘ mummies ’ 
gradually decayed, leaving only the stones and cores. Early in the present 
year, however, apothecia were found on mummied plums ; these were 
naturally infected fruit which had been collected during the winter of 
1918-19, and in January, 1919, were placed in an ordinary flower-pot, which 
was then exposed on the ground in the open and left undisturbed for over a 
year. In the middle of March, 1920, the contents of the pot were examined, 
and it was found that, although the great majority of the plums had decayed, 
leaving only the bare stones, in the debris at the bottom of the pot a few 
black, wrinkled, skin-like bodies remained, one of which still enclosed a 
plum-stone, and growing out of them were apothecia in various stages of 
development. On one of the ‘mummies’ as many as twelve sporophores 
were counted. 
Description of the Sclerotinia found on Mummied Plums. 
The sporophores arose from a thin, wrinkled, sclerotium-like body 
(enclosing a plum-stone or taking the general shape of the stone which had 
fallen out), 0-3 to 0-5 mm. in thickness, and consisting of closely interwoven 
hyphae, together with disintegrated particles of the fruit ; the outer and 
inner surfaces of the sclerotium were black, but the internal hyphae were 
hyaline. 
Each apothecium was stipitate, the stipes measuring from 0-4 to 2-8 cm. 
and in some instances bearing rhizoids towards the base. The lower 
portion of the stipes was dark brown, almost black ; the upper light brown, 
merging into the darker outer surface of the receptacle. The young sporo- 
phorcs were claviform, but the older ones had expanded at the apex and 
become at first crateriform, later plane (but usually with a depressed centre), 
and finally convex, and often split at the margin to form lobes. The 
apothecia examined were, when fully expanded, from 4 to 9 mm. in 
diameter ; the hymenium was brown at first, but later became more or less 
pruinose, and at maturity grey or almost white. The asci were cylindrical, 
narrowed below, rounded above, and when treated with iodine each showed 
a bluish 4 pore ’ at the apex ; each ascus contained eight spores. 
