140 Transactions British Mycological Socieiy. 
IX. MUCOR spp. 
It was practically impossible to distinguish mould growths 
belonging to this genus from those of Thamnidium until the 
forms were isolated in culture. Together with Thamnidium, this 
genus is responsible for the profuse, greyish-white growths upon 
cold-store meat known as “ whiskers,’ but species of Mucor are 
less frequently met with in this connection than are Thamnidium 
elegans and T. chaetocladiotdes. 
Three species of Mucor were isolated from contaminated beef 
and mutton and these have been kindly identified by Prof. 
Lendner of Geneva as 
M. mucedo Linné, 
M. lusitanicus Bonderlein, and 
M. racemosus Fres. 
M. mucedo and M. racemosus are common moulds occurring 
upon a great variety of substrata. 
Like Thamnidium, these fungi grow well at 1-2° C., but apart 
from slight germination of the spores of M. mucedo at — 6° C. 
there has been no indication of growth at this temperature. | 
Tests have not yet been carried out between — 6° and o° C. At 
temperatures just above zero, chlamydospores are formed more 
profusely than at ordinary temperatures. 
M. mucedo and M. lusitanicus grew well and produced 
sporangia at all temperatures between 2° C. and 25° C., but did 
not grow at 30°C. M. racemosus grew at 30° C., but no spor- 
angia were formed at that temperature. 
The behaviour of these species of Mucor on cold-store meat 
is similar to that of Thamnidium and the presence of profuse 
growths of these forms is probably to be correlated with a rise 
in temperature to just above freezing point. Like Thamnidium, 
these species of Mucor do not penetrate the meat to any extent, 
nor do they confer poisonous properties upon it. 
X. SUMMARY. 
(rt) The fungi which occur on cold-store meat coming to 
England from the southern hemisphere have been systemati- 
cally examined. These moulds are: Cladosporium herbarum (the 
cause of meat “Black Spot”), Thamnidium chaetocladioides, 
Thamnidium elegans, Mucor racemosus, Mucor mucedo, Mucor 
lusitanicus, Penicillium expansum, Penicillium anomalum, Sac- 
charomyces spp. together with two new species, Sporotrichum 
carnis and Torula botryoides, and the type species of a new genus, 
Wardomyces anomala. 
(2) A general survey of many forms of Cladosporium has been 
undertaken, with the result that many so-called species of 
Cladosporium including C. epiphyllum are interpreted as strains 
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