The Skeleton of the Fish 



47 



Each vertebra consists of a double concave body or centrum 

 (66). Above it are two small projections often turned back- 

 ward, zygapophyses (71), and two larger ones, neurapophyses 

 (67), which join above to form the neural spine (68) and thus 

 form the neural canal, through which passes the spinal cord 

 from end to end of the body. 



Below in the vertebras of the posterior half of the body the 

 hcemapophyses (69) unite to form the h&mal spine (70), and 



FIG. 29. Pharyngeal bone and teeth of European Chub, Leuciscus cephalus 

 (Linnaeus). (After Seelye.) 



FIG. 30. FIG. 31. 



FIG. 30. Upper pharyngeals of a Parrot-fish, Scarus strongylocephalus. 

 FIG. 31. Lower pharyngeals of a Parrot-fish, Scarus strongylocephalus (Bleeker). 



tnrough the hamal canal thus formed passes a great artery. The 

 vertebras having haemal as well as neural spines are known as 

 caudal vertebra, and occupy the posterior part of the body, 

 usually that behind the attachment of the anal fin (78). 



The anterior vertebras known as abdominal vertebra, bound- 

 ing the body-cavity, possess neural spines similar to those of 



