184 CLASSIFICATION OF MAMMALIA. 



/3. Muridse, tail cylindrical, not bushy. 

 y. Pedetidae, anterior digits 5, posterior 4. 

 B. Spalacidse, anterior digits 5, posterior 5. 

 *. Castoridse, tail flat and scaly. 



2. With imperfect clavicles, or none. 



a. Hystricidae, body covered with spines. 



/8. Leporidse, 2 small incisors behind the 2 superior large ones. 



y. Caviadae, no character in common. 



Sect. c. Without incisor teeth. 

 VI. Edentata. 



1. Tardigrada; with a short muzzle. Bradypus, &c. 



2. Typical Edentata; with an elongated muzzle. Dasypus, &c. 



3. Monotremata ; with marsupial bones and a cloaca. Ornitho- 



RHYNCHUS, &C. 



B. Ungulata. 

 a. Not Ruminants. 



VII. Pachydermata. 



1. Proboscidea ; with a proboscis : incisors projecting ; feet pentadac- 

 tyle. Elephas, &c. 



2. Typical Pachydermata ; feet tetra-, tri-, or di-dactyle. Hippopo- 

 tamus, &c. 



3. Solipeda ; feet monodactyle. Equus, &c. 



b. Ruminants. 



VIII. Ruminantia. 



. 1. Without antlers or horns. Camelus, &c. 



2. With antlers. Cervus, &c. 



3. With horns. Antilope, &c. 



C. Mutica. 



IX. Cetacea. 



1. Herbivora; teeth fitted for mastication. Manatus, &c. 



2. Typical Cetacea ; teeth unfitted for mastication, or wanting. Del- 

 phinus, &c. 



We shall conclude this article with quoting some obser- 

 vations by Mr. MacLeay on the analogies observable between 

 the principal groups of Mammalia, and those into which the 

 class of Birds is resolvable. " Every Mammiferous animal 

 may be reduced to these five orders ; that is, may be assimi- 

 lated, in a greater or less degree, to one or other of the fol- 

 lowing typical forms ; viz. Man, the Lion, the Horse, the 

 Whale, and the Mouse. I shall show hereafter how these five 

 orders form a continued series returning into itself, so as to 

 be a natural group. In the mean time, I must recall to the 

 attention of the reader the orders of Birds as defined and ar- 



