THE WHALEBONE WHALES OF THE WESTERN NORTH ATLANTIC. 



227 



not exactly the same, having a much straighter posterior margin and a knob-like 

 tip joined to it in a manner which makes the figure appear diagrammatic. The 

 dorsal on the foetus itself (37, pi. 3, fig. 1) is short, erect, and has a slightly concave 



FIG. 70. 



FIG. 71. 



FIG. 68. 



FIG. 69. 



FIG. 72. 



MEOAPTERA NODOSA (BONNATEBBE). PECTOEAL AND DOBSAL PINS. 



FIG. 68. TAY RIVER, SCOTLAND. BONES OF PECTORAL FIN. (FROM STRUTHERS.) FIG. 69. PROVINCETOWN, 

 MASS. EXTERIOR OF PECTORAL FIN. (FROM A PHOTO.) FIG. 70. GREENLAND. DORSAL FIN OF A FCETUS. (FROM 

 ESCHRICHT.) FIG. 71. THE SAME, ENLARGED. FIG. 72. TAY RIVER, SCOTLAND. DORSAL FIN. (FROM STRUTHERS.) 



posterior margin like adult Newfoundland specimens, but of course more unde- 

 veloped. (See text figs. 70, 71.) 



Holbb'll describes the dorsal of the adult Keporkak (37, 76) as " low, broad on 

 the side, cut off almost straight toward the tail ; in general, shaped like a broad 

 lump of fat with a knob." Fabricius describes it as " compressed, with a broader 

 base, the apex a little acute, in front sloping upward (swrsum repanda), behind 

 almost perpendicular," but adds " some are obtained, however, which have the apex 

 equally curved, in some longer, in others shorter." Motzfeldt's description of the 

 dorsal fin is as follows (37, 198) : "The dorsal fin of the Kepoi'kak has as a very 

 salient character a protuberance or knob on the anterior (upper) margin." 



Brandt describes the dorsal fin of the Humpback as having " a convex upper 

 border, gradually rising, ending at its highest point behind and above in an obtuse 

 backward-curved tip, below which is a considerable emargination, . . . and 

 then gradually merging into a ridge running forward from the tail." 



Sars's figure of a Finrnark Humpback (80, pi. 2) shows the dorsal fin strongly 

 concave posteriorly. His description is as follows : 



" As in some species of the genus alcenaptera, it is compressed like a scythe, 

 with a rather thick and strongly convex anterior border, and a thin, sharp, and 



