BRITISH LICHENS. 



29 



The most friable specimens by this means can be kept together for any 

 length of time, and will endure the rough usage of the herbarium.* 



A good supply of stoutish cartridge-paper should be kept always at 

 hand, cut into squares of about lin. by 6in., or Gin. by 6in., according to 

 the size of the specimen Lichen it is to receive, allowing room for notes 

 and drawings of the internal characters. A further supply should be 

 ready, about lOin. by 8in., for placing in a portfolio, on which the smaller 

 pieces bearing the specimens can be pinned to allow for easy removal 

 when they are required for examination. These larger sheets will carry 

 several specimens of the same species, and should have the specific 

 name written distinctly at the bottom of the sheet at the left-hand corner. 

 About fifty of these will be sufficient to place in one portfolio, which may 

 be made of strong cardboard, with tape strings to keep it closed. On 

 the back of the portfolio may be written the genus or genera to which it 

 is devoted, and it can be placed as a book in an ordinary book-case. The 

 size given above is that of Mudd's published Fasciculi of British Lichens, 

 and has the advantage of not being too large for an ordinary book-shelf. 

 Half-a-dozen such portfolios will suffice for a beginner, but it is neces- 

 sary to fix on the proper size at the commencement, that no inconvenience 

 may be experienced hereafter by discovering that a different size would 

 have been much more suitable. 



Three bottles to contain the following chemicals for testing the 

 reaction of Lichens : — A solution of iodine, iodide of potassium, and 

 chloride of lime. Three glass brushes, one to be used for each of the 

 chemicals. Further instructions how to apply these will be given in 

 another place, but I would here remark that great care should be taken 

 not to mix these chemicals by pouring one into a vessel which has 

 contained another, without first washing it, or by using the same brush 

 for two chemicals, as the result of testing would be rendered altogether 

 worthless. 



Jlliere to collect Lichens will now require a few remarks. Supposing 

 the student to have provided himself with the necessary appliances just 

 enumerated, he will now undertake his first excursion in pursuit of 

 specimens. He must get well away into the country, at a distance from 

 towns and smoke, for the Lichen loves pure air and free ventilation. It 

 has long since been remarked that they rarely, if ever, attain their 

 perfect maturity in the vicinity of cities or manufactories, where much 

 smoke is found in the atmosphere. Old forests, far-stretching moorland, 

 airy mountain sides, with here and there the jutting rock thrusting its 

 head through the springing heather, the cliffs of sea-shores watered by 

 the spray of the ocean, the stony beds of dry watercourses, such are the 

 places he will find most productive. But if such attractive scenes for 

 Lichen-hunting cannot be visited, the student must make up for the 

 want of such by extra diligence in less promising localities. Some of 

 the most highly-prized species have been found on old rails in the last 



* StiU greater security can be given to f ragUe specimens by glueing them in stout 

 pill-boxes, the wall of the pill-boxes preventing the pressure falling on the Lichen. 



