142 APPLIED BIOLOGY 



sects at this time. Later, after study of insects in Chapter XIV, 

 the students should have practice in identifying common insects 

 with reference to the orders represented by those named above. 

 For the present purpose it will be sufficient to speak of grasshopper 

 group, beetle group, butterfly group, crayfish group, crab group, etc., 

 leaving the technical names of these until later lessons. 



For plant classification, a set of leaves, fruits, branches, bark, 

 etc., of two or more species of some common plants, e.g., oaks, 

 maples, or others available. In the spring of the year, members of 

 the rose family (apple, pear, peach, plum, cherry, quince, wild rose, 

 etc.) will furnish some interesting materials for classification ; and 

 in the autumn there are many composites which might be used in 

 the same way. 



132. Learning Scientific Names. It is not necessary that 

 all the technical names given in the following tables of classi- 

 fication be memorized at one time. The best way to learn 

 them is through use. Only the more important names have 

 been given, and many of them are rapidly becoming com- 

 mon terms. In fact, few people realize that many common 

 names are also the scientific ones. For example, among 

 common plants grown in home gardens : asparagus, spinacia 

 (spinach), aster, alyssum, calendula, centaurea (sometimes 

 called bachelor's button), chrysanthemum, phlox, crocus, 

 cosmos, iris, smilax, narcissus (sometimes called daffodil), 

 tulipa (tulip), hyacinthus (hyacinth), yucca, lilium (lily), 

 viola (violet), petunia, portulaca, salvia, thymus (thyme), 

 zinnia, verbena, heliotropum (heliotrope), all these and 

 many more are the scientific names of the genus in each 

 case; but since for most of these plants there is no common 

 name, the scientific name has become also the common one. 

 This use of scientific as common names should be encouraged 

 whenever there is confusion. Such a case is that of " mari- 

 gold," which has been applied to so many yellow-flowered 

 composites that even gardeners who have not studied botany 

 are learning to use the scientific names calendula, coreopsis, 

 and tagetes as common names. Seed-dealers are helping 



