14 CLASSIFICATION 



Abies; both of the Redwoods to the genus Sequoia, etc. The 

 botanical name consists of the generic name followed by that of 

 the species. We therefore write as the botanical name of the 

 Yellow Pine, Pinus ponderosa; of the Sugar Pine, Pinus lam- 

 bertiana; of the One-leaf Pifion Pine, Pinus monophylla, etc. The 

 generic name is frequently indicated by its initial letter only, and 

 the species name is commonly followed by that of the botanist 

 who first properly applied it. The name of the author is often 

 abbreviated. Varieties, when they occur, are indicated by an 

 additional name following that of the species, a variety being con- 

 sidered a mere form of a species, often brought about by differ- 

 ences in the soil, exposure, or other elements of the environment. 



The next step in our system of grouping is to bring similar 

 genera together into a larger and more comprehensive group, the 

 family. The pines, the firs, the redwoods, the cedars, and many 

 other similar genera are thus classed together as the Pine Family, 

 or Pinaceae, since they possess certain characters in common, 

 such as the cone-bearing habit. There are in all, 280 families of 

 flowering plants, but only 82 of these are represented in the 

 Yosemite National Park. Just as individuals are grouped into 

 species, species into genera, and genera into families, so these last 

 are collected into larger groups, some of which are used in our 

 Analytical Key to the Species. 



But the aim of botanical classification is not merely to arrive 

 at a convenient grouping of plants. Its object is far-reaching 

 and its methods are based upon the fundamental principles of 

 evolution, heredity, and descent. The ultimate aim of systematic 

 botany is to discover a natural system of classification in which 

 all forms of plant life will be grouped according to their 

 relationships. For there is a natural relationship — a blood-con- 

 nection—existing between all plants, just as there is between all 

 people, and the tracing of these connections is at once the most 

 fascinating and the most important of all botanical problems. 

 The student of organic relationships is following the steps through 

 which the innumerable forms of life have been evolved. In his 

 mind's eye he sees the development and modification of plant 

 forms, the survival of the fit, the suppression of the unfit; he 

 traces the development of an organic world. 



Botanical classification, if complete and correct, would express 

 all there is to know concerning the relationships of plants. But 

 our knowledge is sadly deficient. The investigator is often mis- 

 led into assuming that superficial resemblance indicates blood- 

 relationship, or he is falling into other of the numerous pits of 

 deception, and therefore the discovery of the natural system in all 

 its details is a slow and laborious process. Until this task can be 



