LEADING GROUPS OF EXISTING SYSTEMS 155 



SECTION III 

 ORDERS AMONG ANIMALS 



Great as is the discrepancy between naturalists respecting the num- 

 ber and limits of classes in the animal kingdom, their disagreement 

 in regard to orders and families is yet far greater. These conflicting 

 views, however, do not in the least shake my confidence in the exist- 

 ence of fixed relations between animals, determined by thoughtful 

 considerations. I would as soon cease to believe in the existence of 

 one God because men worship Him in so many different ways or 

 because they even worship gods of their own making, as to distrust 

 the evidence of my own senses respecting the existence of a pre- 

 established and duly considered system in nature, the arrangement 

 of which preceded the creation of all things that exist. 



From the manner in which orders are generally characterized and 

 introduced into our systems it would seem as if this kind of group 

 were interchangeable with families. Most botanists make no differ- 

 ence even between orders and families and take almost universally 

 the terms as mere synonyms. Zoologists have more extensively ad- 

 mitted a difference between them, but while some consider the orders 

 as superior, others place families higher; others admit orders with- 

 out at the same time distinguishing families and vice versa introduce 

 families into their classification without admitting orders; others still 

 admit tribes as intermediate groups between orders and families. A 

 glance at any general work on Zoology or Botany may satisfy the 

 student how utterly arbitrary the systems are in this respect. The 

 Regne animal of Cuvier exhibits even the unaccountable feature 

 that while orders and families are introduced in some classes,^^ only 

 orders are noticed in others,^^ and even some exhibit only a succes- 

 sion of genera under the head of their class, without any further 



^ In the classes Mammalia, Birds, Reptiles, and Fishes Cuvier distinguishes mostly 

 families as well as orders. In the class of Mammalia some orders number no families, 

 whilst others are divided into tribes instead of families. In the class of Gasteropods, 

 Annelids, Intestinal Worms, and Polyps, some of the orders only are divided into 

 families, while the larger number are not. 



" The classes Echinoderms, Acalephs, and Infusoria are divided into orders, but 

 without families. 



