96 Bulletin American Museum of Natural History. [Yo\. XXVII, 



FLOWER, 1883. 



'On the Arrangement of the Orders and FamiUes of existing Mammaha.' 

 Proc. Zool. Soc, Apr. 17, 1883, pp. 178-186. 



This classification, which deals only with existing orders, may be regarded 

 as a conservative outgrowth of the systems of Cuvier, de Blainville, Owen, 

 Gill, and Huxley, with special modifications after several other authors. 

 Among its noteworthy features are the following: (1.) de Blainville's three 

 grand divisions are recognized, but Huxley's terms are employed. (2.) 

 The Marsupialia are not divided into suborders for the reason that the 

 Peramelidae were thought to connect the poly'jjrotodont with the diprotodont 

 divisions. (3.) The Edentates are divided as in Flower's work of 1882 

 (P. Z S., p. 358). (4.) In regard to the Sirenia it is stated that the known 

 fossil forms "lend no countenance to their association with the Cetacea; 

 and, on the other hand, their supposed affinity with the Ungulata receives 

 no very material support from them." (5.) Of the Cetacea it is stated 

 that there is "nothing known at present to connect the Cetacea with any 

 other order of JNIammals; but it is quite as likely that they are offsets of a 

 primitive Ungulate as of a Carnivorous type." (6.) "The remaining 

 Eutherian Mammals are clearly united by the characters of their teeth, being 

 all heterodont and diphyodont, with their dental system traceable to a com- 

 mon formula." (7.) All the ungulate groups are comprised within a 

 single order "Ungulata." (8.) The arrangement of the Insectivora, 

 Chiroptera and Rodentia is after that of Dobson; they are thought to repre- 

 sent "an inferior grade of development in the INIammalian series," and to 

 "occupy a central position, connected, as palaeontology seems to show, 

 with the Carnivora on the one hand and the Ungulata on the other" {cf. 

 Gill, 1870). These remarks evidently refer only to the Insectivora and 

 Rodentia (9.) The Carnivora are thought to form "a somewhat natural 

 sequence" from the Insectivora (cf. Gill). The division of the Fissipedia 

 is based on the work of Flower and of ]\Iivart. (10.) "Whether the Lemu- 

 roidea should form part of the Primates (according to the traditional view), 

 or a distinct order altogether removed from it, is as yet an undetermined 

 question, for both sides of which there is much to be said." 



Flower-'s Classification of 1SS3. 



Subclass Prototheria or Ornithodelphia. 



Order Monotremata (Ornithorhynchidse, Echidiiids). 

 Subclass Metatheria or Didelphia. 



Order Marsupialia (Didelphidse, Dasyuridse, Peramelidae, Macropodidae, Pha- 

 langeridse, Phascolomyidse). 



