CETACEA. 



305 



of the skeleton of the hind Hmb. In the Greenland Whale 

 (Fig. 112), there is a proximal, somewhat pear-shaped bone 

 (/), about eight inches in length, and a smaller conical distal 

 bone (/), which may represent the femur and tibia respec- 

 tively, as suggested by their discoverer, Professor Reinhardt.^ 



Fig 112. — Side view ol bones of posterior extremity of Greenland Right Whale 

 {BalcFun tnysticetus), \. from Eschricht and Reinhardt. z" ischium; _/ femur ; 

 t accessory ossicle, probably representing the tibia. 



In Megaptera lo?igi?nana there is but one such bone, and m 

 an adult Fin Whale {Balcejioptera innsathis), sixty-seven feet 

 long, this was found to be only represented by an oval 

 nodule of cartilage about the size of a walnut. Even this 

 is wanting in some species of the group, as B. rostrata. 



No trace of any structure representing the skeleton of 

 the hind limb, beyond the pelvis, has yet been detected in 

 any of the Odontocetes. 



In none of the existing Sirenia are there any rudiments 

 of the hind limb proper, but the extinct Halitheriuin had an 

 ossified femur, articulated to a well-defined acetabulum in 

 the pelvis. 



In the terrestrial and tossorial Edentata the femur is 

 generally short and broad. There is a third trochanter in 



^ See " Recent Memoirs on the Cetacea ; " Ray Society, 1866, p. 134. 



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