238 PRACTICAL BOTANY 



same object, the glass slide, cover-slip, and needles are all to be 

 heated in a spirit-lamp, and the porous pad for the moist 

 chamber is to be well boiled in water. 



Having made these preparations, place a single drop of the 

 dilute, sterilized decoction on the cover-slip : then with a 

 needle, moistened with the sterilized fluid, remove from as pure 

 a tuft of Eurotium as can be found a small number of conidia, 

 and place them in the single drop on the cover-slip : examine 

 under a low power to see that the number of conidia is small, 

 then quickly invert the cover-slip and place it over the round 

 hole punched in the porous pad. Keep the preparation thus 

 made under a bell-glass, and observe it from time to time under 

 the microscope : if the culture be successful, the successive 

 stages of germination and of further development of the Mould 

 may be watched in detail. 



IV. The perithecia, and the archicarps (female organs) 

 which give rise to them, are to be sought for on a mycelium 

 which has already produced mature conidia : the ripe perithecia 

 (Eurotium fruits) may be readily recognized in old cultures on 

 dry bread, as minute yellowish spherical bodies, easily distin- 

 guished by the naked eye. 



A. Remove a small piece of mycelium which has already 

 borne mature conidiophores, and is thus likely to bear young 

 archicarps : moisten it with alcohol, and then wash off in a 

 watch-glass in water as many of the conidia as possible : tease 

 it out with needles, and, mounting in water, examine under a 

 high power. Observe 



1. That the same mycelium which bears the conidiophores 

 also produces relatively thin whip-like branches, with highly 

 refractive contents. 



2. That some of these branches become coiled, at first 

 loosely, but later in a tightly packed spiral of four or five coils, 

 and consisting of several cells : these spirals are the archicarps. 



3. That first one, and subsequently several hyphal branches 

 appear below the closely coiled archicarp, forming an invest- 

 ment round it : the first formed branch is called the poilin- 

 odium (male organ), and comes in close contact with the apex 

 of the coiled archicarp. 



