26 CLASSIFICATION 



5. Acardia, those whose stomach and heart are the same body, as in 

 the Blubber (Medusa), Polypus, &c. 



Classes of Animals according to their Breathing -Organs. 



The 'first class' includes all those animals which have lungs, with cells 

 through the whole, and a diaphragm. 



The ' second,' all those which have their lungs attached to the ribs, 

 so as to confine them to their place. 



The ' third,' all those whose lungs come into the belly and are loose. 



The ' fourth,' all those whose lungs are in their necks, called gills. 



The 'fifth' are reptiles, whose lungs are in their sides 1 . 



Classes of Animals according to Essential and Circumstantial 

 Characters. 



The characters of the ' first class,' which includes land and sea ani- 

 mals, are : — A heart made up of four cavities : essential. The lungs 

 confined to a proper cavity, the enlargement of which is the cause of 

 respiration : essential. Lungs divided into small cells : essential. Re- 

 spiration quick : essential. Viviparous, and I believe the only animals 

 that are [truly] so : essential. Give suck : essential. Parts of gene- 

 ration : in the male, made up of testes and one penis, the testes some- 

 times within and sometimes without the abdomen, but pass forwards : 

 in the female, a clitoris, vagina, uterus, os uteri, fallopian tubes, and 

 ovaria : all essential. Kidneys high up in the abdomen : circumstan- 

 tial. An external canal to the ear : circumstantial. Membrana tympani 

 concave externally: circumstantial. A cochlea: circumstantial. By 

 much the most perfect animals, whether sea or land. 



There is a gradation from the land to the sea-animals, viz. Otter, 

 Seal, Hippopotamus, "Whale. 



The < second class ' is composed of the Bird entirely. I do not know 

 of any animal of this class but has all the characteristics of the bird. 

 They vary less in any of their parts than the first class. 



Lungs : attached to the ribs, that they may move with them ; lungs 

 perforated : membranous bags in the abdomen that receive the air in 

 respiration : something similar to a diaphragm. 



Parts of Generation : ova cmstaceous ; one oviduct ; one penis, and 

 that grooved ; no bladder ; [outlet of the] oviduct [in the female] and 

 penis with the [openings of the] vasa deferentia [in the male] all in 

 the same cavity with the anus. 



1 [By ' reptiles ' Hunter signifies ' creeping tilings,' or Invertebrata in general ; 

 and consequently his fifth class -would include most of those which possess respi- 

 ratory organs, as Insects, Crustaceans, Mollusks, and most Anellids.] 



