PREPARATION OF THE ADHESION CULTURE 79 



3. Breathe into the concavity of a concave slide until 

 small droplets of moisture are visible on the glass. Before 

 this moisture evaporates and while the cover-glass is 

 still wet turn the cover-glass, culture side down, corner- 

 wise, covering the concavity on the slide. 



4. Using the small glass rod or a camel's-hair brush 

 dipped in hot paraffin, neatly seal the cover-glass on the 

 slide so that the cavity will be air tight and the moisture 

 will be retained. Success depends largely on quick work. 



5. Examine with objective No. 7 and ocular No. 1. 

 There should be five to twenty spores or cells on a slide. 

 If more are found, a new culture should be made. It 

 may be necessary to inoculate a second tube of cider 

 from the first to secure the proper dilution. 



6. If you are not familiar with the spores or cells of 

 the organism to be studied, before making an adhesion 

 culture, mount them in a drop of water heavily inoculated, 

 cover with a cover-glass and examine microscopically. 



7. Keep the cultures at room temperature. Examine 

 as often as possible for thirty-six hours and then every 

 twenty-four hours till growth ceases. 



8. Draw as many stages as possible. The time required 

 for spore germination is usually six to forty-eight hours. 



Note. Some molds grow quite extensively in the adhesion culture, 

 even producing fruiting bodies. Very often both the mycelium and fruit- 

 ing bodies show peculiar abnormalities and should never be drawn to repre- 

 sent normal structures. These abnormalities are the result of the 

 peculiar environment. 



9. Failure to obtain growth of the mold spores or yeast 

 cells may be due to imperfect sealing, insufficient moisture 

 at the start or too many cells on the cover-glass. If the 

 adhesion culture fails to grow, a fresh tube of cider must 

 be inoculated before making new adhesion cultures, as the 

 food materials contained in the medium are partly or en- 

 tirely used. In the case of mold spores it is reasonable 

 to expect that any mold spores in the adhesion culture 



