64 THE REASON WHY I 



To Him, no high, no low, no great, no small; 



He fills, He bounds, connects, and equals all.&quot; POPI 



great masters of natural history, differing in their views, produce 

 systems of classification more or less varying from each other. 

 Notwithstanding these difficulties, an approach to uniformity and 

 identity may be obtained, eminently useful where the objects to be 

 distinguished are remarkably numerous. 



162. What are the significations of the terms class, order, 

 sub-order, family, genus, species, &c. ? 



A class is a primary or leading division, a number of being?* 

 having one or more features in common. An order is a sub-division 

 of a class. A sub-order is a further division of an order. Family 

 is a still further division, and is used synonymously with tribe. 

 Genus and species are more limited and definite than family or 

 tribe ; they refer to groups of individuals that agree in all, or 

 nearly all essentials. Genera is the plural of genus. 



163. Species means tribes of animals or plants which have descended from the same 

 stock, or from parentages precisely similar and in no way distinguished from each 

 other. 



The ancients applied the term genus to any collective number of organised beings 

 which are akin to each other, or the offspring cf the same ancestors. The idea of 

 genus was then simple and definite, and just what we attach to the terms kind or 

 kindred. By degrees, the meaning of genus was extended, and it was made to com 

 prehend all such creatures as by reason of some real or fancied resemblance in their 

 form or nature were conjectured to have belonged to one original stock. Such 

 groups were the &quot;dog-kind,&quot; the &quot;cat-kind,&quot; the &quot;ox-kind.&quot; For the more 

 developed state of science, these clauses were too comprehensive, and included 

 tribes so remote from each other that they could not be regarded as the progeny of 

 the same original tribes. The term species was therefore adopted, and made to 

 express nearly what genus now does. 



1G4. According to the LINN JEAN SYSTEM, the whole animal 

 kingdom is ranged under the following six CLASSES : 



I. MAMMALIA (from the Latin mammae, the breasts or teats of a 

 female). Animals with warm red blood, viviparous, and suckling 

 their young. 



II. AVES (birds). Animals with warm red blood, oviparous, 

 an^ feathered. 



