CAKPS. 



587 



ceans, Ascidians, a young Brama, twelve young Boar-fishes, 

 a Horse-mackerel, and one young of its own species. The 

 stomach is coecal; the commencement of the intestine has 

 extremely thick walls, its inner surface being cellular, like 

 the lung -of a reptile; a pyloric appendage is absent. All 

 the bones are extremely thin, light, and flexible, containing 

 very Little earthy matter ; singular is the development of a 

 system of abdominal ribs, symmetrically arranged on both 

 sides, and extending the whole length of the abdomen. 

 Perfect specimens are rarely obtained on account of the 

 want of coherence of the muscular and osseous parts, caused 

 by the diminution of pressure when the fish reaches the 

 surface of the water. The exact depth at which Plagyodus 

 lives is not known ; probably it never rises above a depth of 

 300 fathoms. 



The other less important genera belonging to this family 

 are Aulopus, Ghlorophthalmus, Scopdosaurus, Odontostomus, 

 and Nannobrachium. 



Third Family — Cyprinid^. 

 Body generally covered with scales ; head naked. Margin 



Fig. 271. — Pharyngeal bones and teeth of the Bream, Abramis brama. 



of the upper jaw formed hy the inter maxillaries. Belly rounded, 

 or, if trenchant, without ossifications. No adipose fin. Stomach 



