498 BIOLOGY. 



3088. The complete subdivision of animals, according 

 to the organs of sense, would consequently stand thus : 



I. Dermatozoa . . Invertebrata. 



1. Oozoa . . . Protozoa. 



2. Glandular animals . Conchozoa. 



3. Cutaneous . . Ancyliozoa. 



II. Glossozoa .... Pisces. 



III. Rhinozoa .... Reptilia. 



IV. Otozoa .... Aves. 



V. Ophthalmozoa . . . Thricozoa. 



3089. Unto these organs of sense the anatomical, or 

 internal parts, are subordinated, and range parallel to 

 them in a striking manner. The following is their order 

 of succession in accordance with that of their origin : 



1. Intestinal system. 



2. Vascular 



3. Respiratory 



4. Osseous 



5. Muscular 



6. Nervous 



3090. That the vegetative systems are correctly 

 arranged after this manner, is proved chiefly by their 

 order of development in the animal series. 



3091. The animals, occupying the lowest grade, are 

 nothing but an intestine, which is in many instances 

 scarcely separated or distinct from the tegument ; they 

 are devoid of vessels and branchiae, and are barely pro- 

 vided with self-substantial ovisacs. Their body consists 

 of one or two concentric cysts of an homogeneous and 

 transparent substance Intestinal animals, Protozoa. 



3092. When the intestine is freed from the mass of 

 the body, both then obtain the form and substance of tegu- 

 mental cysts, whereof the external being only an intes- 

 tinal tunic, thus represents the peritoneum. They are 

 now, however, united by means of a vascular system, 

 which is again surrounded by a cyst, and thus by a 

 pleura. Their body consists of three concentric cysts ; 

 intestine, peritoneum, and pleura. It contains too a liver 

 and self-substantial sexual parts Vascular animals, 

 Conckozoa. 



