68 R. w. SHUFELDT. 



"Phylogenetic Tree" for the Glass, — but we have not the requi- 

 site knowledge, much less the material, at this time. 



There have been a great many classifications of the Mam- 

 malia proposed, the earliest ones dating far back into remotest 

 history. Crude and unnatural, the first attempts in this direction 

 are now considered by systematists as the mere antiquities and 

 curiosities of biological literature, and it is only within compara- 

 tively recent times that mammalogists are arriving at anything 

 like unanimity of opinion in the matter, which is the best evi- 

 dence that we have that we are gradually approaching the long- 

 desired goal of the true and natural scheme of arrangement for 

 the Class. It is now at least safe to predict that we are upon 

 the right road, and any conscientious work done along that 

 road ought to prove to be of use and value, as well as a real 

 contribution to the subject. 



It would be quite impossible, if not altogether out of place, 

 to discuss in the present paper the merits of any of these 

 earlier attempts to classify the Mammalia, such as the ones pro- 

 posed by Linnaeus, Ray, Cuvier, Ovs^en, Huxley, Flower, 

 Milne-Edwards, Gill and others; nor will it be expedient to 

 enter into a discussion of the systems proposed by modern 

 writers on mammalian taxonomy, as that, too would require the 

 limits of a small volume to properly treat of such a theme. 

 I have carefully studied and taken into consideration all such 

 contributions while engaged upon the arrangement here pro- 

 posed, and for this the student must accept my word. Perso- 

 nally I have studied the habits, history, and structure of mam- 

 mals, almost continuously, for the better part of half a century, 

 and it was not until I had passed through such a schooling, 

 both in the museums and in the field, that I felt at all com- 

 petent to touch upon the subject of their probable relations to 

 each other and venture to offer a scheme for their arrangement. 

 I trust the present work will bear me out in this statement. 



