ZOOLOGY. 545 



3303. The nervous system when liberated from the 

 vegetative organs is, or consists of, the myelon (spinal 

 chord) and the encephalon, i. e. brain. 



3304. These animals are therefore Osseous, Muscular, 

 and Encephalic animals, whereupon the senses are pro- 

 portionately developed, and constitute the basis of the 

 highest animal forms Sarcozoa. The Dermatozoa are 

 asarcose oxfeshless animals. 



3305. With the sudden appearance of the animal 

 systems all organs of the head, such as tongue, nose, 

 ears, and eyes, are also developed ; no asarcous animal 

 has nostrils. Now these parts, especially the nostrils, as 

 marking the terminal extremity of the vertebral column, 

 make up the head Cephalozoa, or Cephalic animals. 



Class 10. Osteozoa, Glossozoa. 



3306. The animals, in which the osseous system for 

 the first time makes its appearance are, the Fishes. 



The Fish alone has more bones than any other animal. 

 It has dorsal rays, which are wanting in all others. 



3307. The animal systems are for the first time 

 slightly separated from each other. Bone, muscle, and 

 nerve are rather a gelatinous mass, which only bids fair 

 for becoming something higher ; on this account the 

 bones are frequently but soft cartilages or tendons, the 

 muscle composed of white fibres like those upon the 

 intestine or vessels, the nerve thick, oleaginous, and soft 

 in texture, while the brain is in its constituent parts 

 hardly comparable with that of the Thricozoa. 



3308. The muscles of Fishes are not yet perfect in 

 character, since they are devoid of individualization and 

 red colour, and their fibres run mostly parallel with each 

 other without uniting into tendons. Their muscular 

 body is a muscular wall. 



3309. The Fishes, ranking upon the first stage of the 

 Sarcozoa, repeat the same stage of the preceding circle, 

 and thus the Infusoria, Mussels, and Worms ; or the 

 stomach, veins, and branchial rete or network ; further- 

 more, the vitellus, ovary, and skin, which systems must in 

 them accordingly predominate. 35 



