192 SECTIONAL ADDRESSES 



of a common laboratory-method of obtaining growth. It is directly 

 owing to Duggar's investigations that the mushroom-growing industry 

 began its great development in America, where the annual production 

 is now 17,000,000 pounds. 



At the present time several firms in this country produce spawn. 

 This so-called pure-culture spawn may be tissue-spawn or spore-spawn — ■ 

 it is not possible to judge from some of the advertisements. Most of 

 the spawn on the British market is produced either in this country, in 

 America, or in France ; it is sold in bottles, cartons and other receptacles 

 and very little brick-spawn is now used. All firms keep their methods 

 secret, but it is said that while some germinate the spores as shed, others 

 use the flesh of the stem, or gills. It may seem an anticlimax to add that 

 the secret surrounding the germination of mushroom spores is simply 

 a time factor, for they will grow on a wide range of media if sown fresh 

 and left for from ten to fourteen days. 



By the adoption of the pure-culture method it is possible to perpetuate 

 a satisfactory strain and this will remain as true as that of any horti- 

 cultural plant. Thus a good deal of the former indefiniteness about 

 the crop to be obtained is obviated. But judging from the displays in 

 London shops there are too few strains now grown. It should be possible 

 and profitable to get away from the three or four stereotyped forms, one 

 at least of which appears to be American. 



With the coming of the motor-car there was immediately a fear of a 

 shortage of manure for making mushroom-beds, and it cannot be said 

 that the danger has decreased with the years, now that even cavalry is 

 being mechanised. The attention of scientific men and growers is being 

 paid to the possibility of a substitute, but so far with no outstanding 

 success. 



Mushroom growing is not an easy business if it is to be carried on 

 year after year. There seems to be a popular idea that mushrooms can 

 be successfully grown only in darkness, and that sheds, tunnels, 3 caves 

 and suchlike must be available. It is true that caves — if properly ven- 

 tilated — are very satisfactory as is abundantly proved by the outstanding 

 results obtained by French growers in the famous caves in the environs 

 of Paris. 4 However, it is rare to find mushrooms growing naturally in 

 anything but full daylight, and a good deal of commercial growing is 

 carried on in the open in the south-east of England. Indeed at the time 

 of the first development of the sites of the South Kensington Museums 

 the neighbourhood was well known for the mushroom crops of its market 

 gardens. 



The Japanese and Chinese are great consumers of fungi, and many 

 species, fresh, dried or canned, are on sale in the shops. The most 

 appreciated species in Japan is Cortinellus edodes, ' Matsu-dake,' and 

 annual picnics are held for gathering it in the Pinus densiflora forests, 

 an age-long custom frequently alluded to in poetry and in pictorial arts. 



3 The best known of these in the British Isles is the Scotland Street Tunnel at 

 Edinburgh. 



4 The cultivation of mushrooms is now carried on in the caverns under Hamlet's 

 palace, Kronenberg, at Elsinore. 



