10 CALIFORNIA STATE COMMISSION OF HORTICULTURE. 



they belong. Everything that lives, breathes, walks, flies, or swims, 

 everything with fur, feathers, or scales, we know belongs to the 

 animal kingdom. But among animals there are great dissimilarities. 

 As stated, one great portion has an articulated backbone or vertebra? 

 and another, and more important class, has none; so our great animal 

 kingdom branches off into two forks, and these are known as subking- 

 doms. It is still easy to tell to which of these an animal belongs, for 

 every child can tell at a glance whether it has a backbone or not. So 

 far our task is easy, but there are great points of difference, even among 

 backbone and non-backbone animals. The snake, the bird, and the 

 horse all have backbones and, therefore, all belong to the subkingdom 

 Vertebrata, but they have little else in common, so the Vertebrata are 

 again divided into four classes mammalia, birds, reptiles, and fishes. 

 Each of these again is divided and subdivided according to well-marked 

 peculiarities common to the whole group, until we get down to the 

 species and the individual. This has been explained in the preceding 

 pages, where we have followed the insect down to its place in the 

 animal kingdom, through the Invertebrata, Arthropoda, and Tracheata. 

 So by means of the following stages we can trace an insect down to its 

 natural place: 



Kingdom, 



Subkingdom, 



Branch, 



Class, 



Order, 



Family, 



Genus, 



Species, 



Individual. 



To illustrate, we will take our common swallow-tailed butterfly, and 

 work it down to its final place: 



Kingdom = Animal. 



Subkingdom = Invertebrata. 



Branch = Arthropoda. 



Class = Hexapoda. 



Order = Lepidoptera. 



Genus = Papilio. 



Species = Rutulus. 



All of the species Rutulus are alike. Where there are slight vari- 

 ations, these are not fixed, but found only in the individuals. With 

 different members of the genus Papilio, however, there are very distinct 

 differences, yet all have a general similarity, enough to group them in 

 one genus, so all the members of the genus Papilio have characters in 



