Vi PREFACE. 



ural orders of animals. The mode of arrangement, 

 or classification, of these into larger groups is a 

 matter of altogether secondary importance." 



While the information herein contained is ex. 

 pressed without technicality, the common names of 

 orders and families are in every case followed by 

 the scientific term,, for the convenience of the in- 

 structor or advanced student. So also as regards 

 classification : the groups of animals are arranged 

 in an order that represents the latest knowledge of 

 the various forms that constitute them ; thus, the 

 plan of Professor Flower has been followed in the 

 mammals ; that of Dr. Gill in the fishes ; and Pro- 

 fessor Cope, in the batrachians and reptiles. The 

 student is first presented with the lowest forms, as 

 being the easiest understood, and so led to others 

 more complex ; this plan being considered the 

 most philosophical and natural. 



The general characteristics of each branch or 

 order are plainly defined, why and how they differ 

 from preceding ones shown, and then examples are 

 given of the individuals constituting the group that 

 have been selected for their availability as repre- 

 sentative forms, and for certain peculiarities that 

 will be most readily impressed upon the memory. 



It is probably the experience of every teacher 

 in zoology that little or no advancement, can be 

 made unless the student can be thoroughly inter- 

 ested in the work, and to this end material has been 



