Notes . 
565 
PENICILLIUM AS A WOOD-DESTROYING EUNGUS.— - 
Spores from pure cultures of Penicillium were sown on sterilized 
blocks of spruce-wood, cut in March, and were found to grow freely 
and develop large crops of spores on normal conidiophores. Sections 
of the infected wood showed that the hyphae of the mould entered the 
starch-bearing cells of the medullary rays of the sap-wood and con- 
sumed the whole of the starch. The resin was untouched. In culture 
three months old the hyphae were to be seen deep in the substance 
of the wood passing from tracheide to tracheide vid the bordered pits. 
Control sections, not infected and kept side by side with the above, 
contained abundance of starch, and no trace of hyphae could be 
detected in them. 
The observation appears of interest in several connexions. Peni- 
cillium is one of our commonest moulds, and undoubtedly plays 
a part in the reduction of plant debris to soil- constituents; how far 
it can itself initiate the destruction of true wood, or how far it merely 
follows on the ravages of other fungi, bacteria, &c., is unknown. 
There are strong grounds for believing that it destroys the oak of 
casks, &c., but since these are impregnated with food-materials this 
is not very surprising. Trabut 1 has shown that Penicillium will grow 
in solutions containing 2-9*5 P er cent * °f CuS 0 4 , and other evidence 
exists showing how remarkably resistant this mould is, and how little 
organic matter it needs for life. 
Dubois 2 showed that Penicillium , or a closely-allied form, not only 
lives in strong solutions of copper, neutralized with ammonia, but will 
erode metallic copper and bronze if transplanted thereon. 
Jonssen 3 found Penicillium living in one-tenth normal sulphuric 
acid solution, and gives some interesting facts regarding the sulphur- 
containing oil-drops in its protoplasm, and other statements concerning 
oil in this fungus occur in the works of De Bary, Brefeld, Pfeffer, &c. 
Gerard 4 gives proof that Penicillium can liberate butyric acid from 
mono-butyrine, and evidence that this is due to its power of forming 
a lipase or fat-splitting enzyme. 
Lesage 5 gives striking instances of the resistance to externa 
1 Bull, de la Soc. Bot. de Fr., xlii, 1895, 1. 
2 Comp. Rend., 1890, cxi, p. 655. 
3 Bot. Centr., xxxvii, 1889, p. 201. 
4 Bull, de la Soc. Mycol. de Fr., xiii, 1897, p. 182. 
5 Ann. des Sc. Nat., Ser. 8, T. i, 1895, p. 309. 
