2\2 THE AMERICAN MONTHLY \^i^\^i., 



bactorial forms of funjii. Tliese beinps are thus almost rvcrv- 

 wluTt* for wtal or woe, ami the soieiitiflc modes of Hvinti that 

 are coming into vogue are having to recognize them as amoiii: 

 tlie most potent agencies that afVect us. 



There are many mo(U's of studying these interestin<: plants. 

 and th(»se who wish to penetrate deeply into them will find niniiy 

 ttH-linieal guides to assi.st them. For the direetit)n of sueh, a par- 

 tial hihliograj)hy of the subject will be ajipended. For a be- 

 ginning, liowever, fungi can be easily cultivated on almost any 

 organic substance which is kei)t moist and warm enough. In- 

 fusions of various sorts, such as: tea, hay, beef, oats, cracker, 

 and other sueh common stull'. made by heating the substances 

 to boiling and then setting them aside in tumblers covered with 

 glass plates, will in a few days l)e found to contain moulds 

 and i>erhaps also infusorial animals. Another mode of culture 

 is by the use of Pasteur's lluid.* This is n)ade of sugar, am- 

 monium tartrate, and traces of suli)liur and potassium salts dis- 

 solved in water. If this stands in a wide shallow vessel open 

 to the air lor a few days, the vessel will be covered with a white 

 film, this will soon become green in spots and then soon there- 

 after the green will cover the entire surface. The green color is 

 due to the spores which easily become dislodged and then (loat 

 in the air. From the green matter thus obtained you can cul- 

 tivate this mould under any conditions you may desire. 

 I. — Penicillium glaucum. 



This is the name of the green mould which is so well known 

 in all housekeeping. As far as the naked eye can take one, the 

 mould ai)pears as a felted, green, or white membrane. In the 

 younger stages of the growth, it is in small spots scatter»'d 

 everywhere on the culture tluid ; later, these coalesce and their 

 identity is lost. The surface of the older growths has a velvety 

 appearance. This is due to the innumerable "hyjdia'," which 

 are minute threads rising above the mat like the "i)ile" of vel- 

 vet. If you blow forcibly over the green surface you can see a 

 powdery dust fly off. It is the conidia or s]»ores which are 

 jtroduced on the hypha-. 



•Pafitenr's Flnid is made in the proportion: — 



Wat^T ll.Vl parts: cjini- sugar, T'lO part.s; aminoninni tartrate, ^O parts; 

 pota-ssium phf»sphat«', 10 parts; (-al(-iiiiii phosphat(% 1 i)art; niagnesiiiiii sul- 

 phate, 1 part. 



