viii SUGGESTIONS TO STUDENTS 



cedes the Index, where they are defined. In order to use 

 the Keys with success, accuracy of observation of the speci- 

 men and careful attention in following the Key are of 

 primary importance; the flowers should be completely open. 

 It is always desirable to read both a and b and c when 

 present, before choosing between them. At times you will 

 have to exercise your best judgment and use the one which 

 seems to fit best ; usually, however, there will be no difficulty 

 in determining which to take. 



Many plants are variable, so where there are several 

 plants always obtain an average one, and one which is in 

 full flower. When you are sure that you have a Violet, 

 for instance, you can turn to the Violets without using one 

 of the four general Keys, or when you know the flowers of 

 a certain Family as the Mustard, Pea, Carrot, or Thistle 

 Family, you can turn to the Key of that Family. After 

 using the Keys for a time you will find many "short cuts" 

 in finding out the individual plant, but at first you should 

 begin as suggested above. The asterisk (*) after the scien- 

 tific name indicates that the plant is cultivated, although in 

 some cases it may be found growing wild. 



Should you find some plants which you cannot determine 

 I shall be very glad to have them sent to me for identifica- 

 tion; I shall likewise appreciate any suggestions which may 

 be offered to improve the Keys, and any suggestions as to 

 omissions. Should this work meet with sufficient approval 

 it will be followed by the descriptions of the species. An 

 abridged copy containing only the Spring Flora has been 

 published for those wishing such an edition. 



THE AUTHOR. 



