FOSSIL AND RECENT 



61 



un1-2 



ep1-3 



nsp pu3 



pu 3+4 



Fig. 28. Tarpon atlanticus (Cuvier & Valenciennes). Caudal skeleton in left 

 lateral view. Based on a young individual 87 mm S.L. 



parapophyses are found throughout the abdominal region. Those upon the last 

 eight abdominal centra become progressively longer. Pleural ribs are attached to 

 the ventro-posterior aspect of all parapophyses, including those associated with 

 the neurocranial centrum. 



Epineurals are attached to the bases of the neural arches throughout the abdominal 

 region. In the caudal region the dorsal series of intermuscular bones have forked 

 bases which are attached to the bases of the neural arches. Epipleural (ventral) 

 intermuscular bones attach to the dorsal surface of the parapophyses. In the 

 caudal region ventral intermusculars are attached to the bases of the haemal arches 

 by tough connective tissue. The ventral intermuscular bones of the anterior 12 

 vertebrae are attached to the lateral face of the centrum and there are small pro- 

 jections upon the centra to receive the intermuscular heads. Thus in the extreme 

 anterior region the intermusculars are epicentral in position. An intermuscular 

 bone which is attached to the exoccipital appears to lie in series with these epicentrally 

 placed intermusculars. In the caudal region fine intermuscular bones are attached 

 to the centre of each centrum by a narrow strand of connective tissue and are there- 

 fore to be regarded as epicentrals. Thus there are three series of intermusculars 

 in the caudal region ; dorsal, epicentral and ventral intermusculars. 



Between the neural spines of the first 22 vertebrae there is a series of 23 supra- 

 neurals. All but the first are slender and tubular. The first is solid, very broad, 



