OF ANIMALS. 27 



Liver: divided into two lobes; cyst-hepatic duets 1 . 



Organ of Hearing : little external passage to the ear ; membrana 

 tympani convex externally, and with but one bone [ossiculum auditus] ; 

 no cochlea 2 . 



Feathers ; wings ; two legs ; long neck ; a bill ; a membrana nicti- 

 tans ; bursa [Fabricii]. 



None of this class are entirely sea-animals ; but it may be said to 

 possess in some measure three elements, viz. air, earth, and water : but 

 they live no more in the air than other animals ; it is only for their 

 progressive motion 3 . 



In the ' third class ' we shall find some parts similar [to those in the 

 second]. The third class may be divided into two ; for they are not 

 exactly alike, but one seems to partake of the second and third, as it 

 were, made up of both. The first division of the third class, then, 

 is the Lizard and Serpent kind. They have : — 



Heart : two auricles, one ventricle, two aortas which unite in the 

 abdomen. 



Ltmgs : loose bags, which lie in the thorax and abdomen, only par- 

 tially divided 4 . No diaphragm. 



Kidneys : in the lower part of abdomen. No bladder 5 . 



Parts of Generation : two penises, which are in the tail, and are 

 grooved. Some are oviparous, eggs without [hard] shells ; others are 

 viviparous, but not as in the first class. 



Some have legs, others none ; some a membrana tympani which is 

 convex outwardly, as in the lizard 8 ; others none, as in the snake 7 . 



The other part of this class, which may be called the ' fourth,' or the 

 Amphibious, is more fishified than what the fish of the first class 

 [Cetacea] are. The common amphibious animals are frogs, turtles, 

 crocodiles, &c. This [class] is very similar to the two former, and is 

 nearly, as it were, a mixture of both ; yet the most essential parts 

 belong, or are similar to the last : — 



Heart: two auricles, one ventricle 8 , as in the Third. 



Lungs : as in the Third ; aorta as in the Third ; no diaphragm. 



Kidneys : as in the Third. 



1 [Hunt. Prep. No. 816.] 2 [Hunt. Prep. No. 1581.] 



3 [Air is not more essential to the life of birds than of other animals ; their espe- 

 cial relations are to air as a medium of locomotion.] 



4 [Hunt. Prep. Nos. 1105-1109.] 



5 [This character applies only to serpents, not to all lizards.] 



6 [Hunt. Prep. No. 1576.] 7 [It exists, but adheres to the skin.] 



b [Hunt. Prep. Nos. 915-919 (Amp7iiuma), {Chelone mi/das) : the preparation of 

 the heart of the crocodile, No. 921, is so dissected as not to show the complete sep- 

 tum of the ventricular cavity, peculiar to the Crocodilia, among reptiles.] 



