114 Transactions British Mycological Society. 
the cause of “Black Spot” to Oidium carnis but this is doubt- 
less another, but incorrect, name for Cladosporium herbarum. 
Tabor (x7) has recently contended that “Black Spot” of meat 
may be produced by many different fungi, but in our experience 
there is no satisfactory evidence for this statement. The fact 
that he has invariably failed to obtain growth from “Black 
Spots”? shows that his methods are imperfect, and his con- 
tention that the “Black Spots”’ are due to the death of various 
mould fungi in the meat cannot be substantiated. In practically 
every case that came under our observation, the “ Black Spots” 
on meat contained living mycelium which gave rise, under 
suitable conditions, invariably to Cladosporium herbarum, and 
to no other fungus. Furthermore, the only fungus with which 
we have been able to reproduce “‘Black Spot” on meat in cold 
storage is Cladosporium herbarum. It often happens that other 
mould growths of a more superficial character, such as Pem- 
cillium and Mucor, are superimposed upon “Black Spot,” but 
in no case have they had anything to do with the very well- 
defined trouble of “ Black Spot.” 
While this work was in progress, Monvoisin (13) in France, was 
making a similar investigation unknown to us. He published 
a short paper, the results of which agree in the main with our 
observations. The fungi he specifically mentions as occurring 
on cold-store meat are Thamnidium elegans, Mucor mucedo, 
Rhizopus sp. and Penicillium glaucum. At a much earlier date, 
Talayract (x8) had recorded the occurrence of Penicillium, Sporo- 
trichum, Mucor spp., Dematium, and pink yeasts upon imported 
meat which he had seen in the London docks, the Dematium 
mentioned here being doubtless Cladosporium herbarum. 
Quite recently another French worker, Bidault(2), has pub- 
lished a brief account of the moulds of frozen meat. The forms 
of commonest occurrence according to him are much the same 
as those found by us, but in our experience Botrytis spp. and 
Stysanus stemonitis have not been seen. On the other hand, 
some species commonly found by us are not recorded by him. 
Details of experiments on the growth of these moulds at low 
temperatures are not given, but he states that Chaetostylum 
Fresenii (= Thamnidium chaetocladioides) and Hormodendron 
cladosporioides (= Cladosporium herbarum) will grow slightly at 
— 10° C., and that others will grow between — 6° and 0° C. 
It was shown in the previous report (3) that the “‘ Black Spot” 
fungus possessed the remarkable property of growth at — 6° G. 
Another of these meat moulds, Torula botryoides, was also found 
to develop at this low temperature, and more recently certain 
others have given evidence of slight power of development at 
— 6° C, All these forms grow readily at 0° to 2° C., and perhaps 
