CULTIVATION OF MUSHROOMS. 261 



There are some brands of spawn, that is, those manufactured by- 

 certain houses, which rank very high among those who know the 

 qualities and the value of good spawn. Some large growers send 

 direct to the manufacturer for their spawn, and where it is to be 

 obtained in large quantities this is a desirable thing to do, since the 

 cost is much less. Where obtained from seedsmen in large quanti- 

 ties, the prices are much lower than where small quantities are 

 purchased. One of these brands of spawn, the Barter spawn, is for 

 sale by several different dealers, by Mr. H. E. Hicks, Kennett 

 Square, Pa., by Henry F. Michell, 1018 Market street, Philadelphia, 

 and by Henry Dreer, 724 Chestnut street, Philadelphia. Another 

 brick spawn, known as " Watson Prolific," is for sale by George C. 

 Watson, Juniper and Walnut streets, Philadelphia. James Vicks 

 Sons, Rochester, N. Y., and Peter Henderson & Co., New York 

 City, have their spawn manufactured expressly for their trade. 



The Barter spawn is said to be made fresh every year, or every 

 other year. Instead of the ** continued culture" of spawn, 

 that is, inoculating the bricks each succeeding year from the same 

 line of spawn, which is, as it were, used over and over again, a re- 

 turn is made each year, or in the alternate years, to the natural or 

 virgin spawn, which is obtained from old manure heaps. In this 

 way, the Barter spawn* is within two to three, or four, generations 

 of the natural spawn. The number of generations distant the brick 

 is from the natural spawn, depends upon the number of times it may 

 have been multiplied before it is inoculated into the bricks. That is, 

 the natural spawn is probably first grown in large beds in order to 

 multiply, to produce a sufficiently large quantity for the inoculation 

 of the immense number of bricks to be manufactured. For it is 

 likely that a sufficient amount of natural spawn could not be ob- 

 tained to inoculate all the bricks manufactured in one year. If a 

 sufficient amount of the natural or virgin spawn could be obtained 

 to inoculate all the bricks of one year's manufacture, this would pro- 

 duce a spawn removed only one generation from that of natural 

 spawn. 



If the natural spawn were first grown in beds, and from here in- 

 oculated into bricks, this particular brick spawn would be removed 

 two generations from the natural spawn. So the number of times 

 that successive inoculations are made to multiply the spawn, the 

 manufactured products are removed that many generations from the 

 natural spawn. Where recourse is had to the natural, or virgin 



* I have not learned the history of the other kinds of spawn referred to above. 



