550 
PLATE XLII. 
Page 
Fig. 1. Crenacantous MAsor, Agassiz, : ° ° ° 5 3 . 334 
Probably posterior dorsal spine. 
Limestone, Bristol, . 5 0 Ex. coll., Bristol Museum. 
Fie, 2. Crenacanruus magor, Agass., . 334 
Probably anterior dorsal spine. 
» 26. Section across the latter near the basal extremity. 
» 4@ 5 ON near the point. 
» 2d, Enlarged representation of surface markings. 
Limestone, Armagh, ; 0 ex. coll, Enniskillen Collection. 
Natural size. 
