Examination of Fungi, 6i 



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peculiarities presented by each species on examina- 

 tion, to sketch and describe all its features, and not 

 only those brought into prominence in the text-book 

 used. An imperfect examination is always eventually 

 regretted, and really amounts to so much time wasted, 

 as sooner or later it has to be done over again. 

 Specimens that have been dried require to be soaked 

 in water until fully expanded before their structure 

 can be seen, then, in the case of minute species, they 

 should be carefully examined under a one-inch objec- 

 tive, and afterwards a section should be cut for 

 examination under a higher power. A good quarter- 

 inch objective is generally sufficient to define clearly 

 the minute characters presented by spores, as the 

 number and arrangement of septa or markings on 

 the surface of the wall. Many thin-walled spores, 

 gonidia, and hyplise collapse when dry, and frequently 

 remain in this condition after the funsfus as a whole 

 has expanded in water. In such cases, in fact under all 

 circumstances, it is advisable to place the spores or 

 sections intended for microscopic examination in a 

 weak solution of ammonic hydrate (liquid ammonia) 

 instead of water on the slide, when in most cases the 

 various portions will become fully expanded in a very 

 short time. But if this does not take place, place a spring- 

 clip over the cover-glass and raise the liquid to boiling 

 point over a spirit lamp. Specimens expanded in this 

 way do not collapse when mounted in glycerine jelly, 

 whereas spores that have been expanded in water only 

 frequently do so. In the microscopic examination 

 of moulds it is important to observe the method of 

 attachment of the gonidia, and also to notice whether 



