Fishes of the Western North Atlantic 



15 



Figure 3. Caudal fin of: top, Acipenser oxyrhynchus (sturgeon), showing especially the extended scaly axis and 

 fulcral scales, drawn by E. N. Fischer; lower left, Sahelinus alpinus (Arctic charr), from eastern Greenland, 

 drawn by Jessie H. Sawyer, lower right, Lepisosteus (longnose gar), after KoUiker, combined with drawing 

 of L. osseus by Jessie H. Saw}er, with fulcral scale from upper margin, about x 2. 



The sturgeons head the list, with the gars in second place, for while the known 

 fossil record does not reach back beyond the upper Cretaceous for the living repre- 

 sentatives of either of these groups,*' fishes that seemingly were ancestral to both of 

 them are known from as far back as the Upper Triassic. The Isospondyli and the 

 Iniomi come next in recorded antiquity; the Elopidae (tarpon and ladyfishes), Clupei- 

 dae (herrings), and Chanidae (milkfishes) are known from the Lower Cretaceous, with 

 the Albulidae (bonefishes) and even the Myctophidae (or some closely allied genera) 

 and Aulopidae known from the Upper Cretaceous. There is no known fossil record 



46. Wilimovsky {go: 1205—1208, pi. 132) has described and figured an undoubted sturgeon from the Upper Creta- 

 ceous of Montana. 



