A c tinop terygii Cliondrostei. 



101 



These fishes all have strongly heterocercal tails, bnt there 

 is one family (that of Catopteridse) in the Trias, in which the 



FIG. 143. Etii-i/notus crenatus. Agassiz (restoration by Dr. R. II. Traquair) ; " Cement- 

 stones," Carboniferous Series of Scotland. 



tail is henii-heterocercal and the rays of the dorsal and anal Wall-case, 

 fins are nearly as few as their supporting cartilages. They are ^- 8> an( i 

 represented by Dictyopyge, from Europe, North America, and 

 Australia, and by Catopterus from North America. They are 

 fc a distinct link between the Chondrosteans and the great 

 majority of Mesozoic fishes. 



Here are also placed the Belonorhynchidae, which are 

 elongated fishes with much-produced snout, diphycercal tail, 

 and the trunk only armoured with four longitudinal rows of 

 scutes one dorsal, another ventral, and one along the course of 

 the " lateral line " on each side. Skeletons of the small Belono- 

 rhynchus striolatus from the Upper Trias of Raibl, Carinthia, 

 and fine skulls of larger species from the Lower Lias of Lyme 

 liegis and the Upper Lias of Wiirtemberg, are exhibited. 



Table-ease, 

 No. 40. 



FIG. IM.rtatysomus striding, Agassiz (restoration by Dr. K. 11. Traquair) ; Magnes : an 

 Limestone, Durham. 



