162 A BOOK OF WHALES 



Me^aptera is not widely removed in its structural 

 characters from Balt&noptera. Externally it is to be 

 distinguished by its more ungainly form, its very long 

 pectoral limbs which are fringed along the anterior 

 margin, and by the low dorsal fin. The tail is also 

 fringed with numerous serrations ; but they are un- 

 connected with deeper lying parts. In the case of 

 the flipper the rounded processes of the margin are 

 the outward expression of the bulging of the inter- 

 phalangeal cartilages. 



The skeleton of Megaptera has been described by 

 many ; the most elaborate account of it with which 

 I am acquainted is contained in a paper by Sir John 

 Struthers.* Generally speaking the differences from 

 Balanoptera are neither numerous nor important. 



The seven cervical vertebrae are not united ;t 

 there are fourteen dorsals, ten lumbar, and twenty-one 

 caudals. 



The sternum of Megaptera is not widely different 

 from that of Bal&noptera. It has a somewhat 

 cruciform shape. The first rib (and that only) is 

 attached to it by a single continuous ligamentous 

 connection ; there are not two distinct attachments 

 as in Baleznoptera musculus, as described by Struthers 

 and Delage (quoted on p. 157). 



The scapula is peculiar in the practical absence of 

 both acromion and coracoid process ; it is moreover 



Jouin. Anat. Piiys., vols. xxii., xxiii. More recently Gervais 

 (Nouv. Arch. Mus., 1888, p. 199) has dealt with and figured the osteology 

 of a form from the Persian Gulf which he calls M. indica. 

 t Occasionally, to a variable extent, they are in later life. 



