180 PROCEEDINGS OF THE ACADEMY OF 



measures one-third this height. The length of the diapophyses is considerable, 

 and similar in both. Rudolphi represents eleven chevron bones, and the 

 anterior ribs are not flattened, or furnished with an inner process in his 

 figure. 



In the M. gigas, the spinal canal is relatively larger, and the cervical 

 superior and inferior transverse processes of one side are more symmetrical 

 and similar. 



An American fin-backed whale has been named Megaptera americana, 

 from a very brief and indefinite description in the Philosophical Transactions, 

 I. p. 11. A species named on such a basis can never be recognized; but, if 

 we must accept it, the only character given, the relative lengths of the body 

 and fin, are entirely at variance with those of the present species : the length 

 of the latter is said to be one-third of the total. 



Supposing the reduced number of vertebra? and chevron bones to be the 

 result of accident, and the form of the anterior ribs to have been unnoticed 

 by Rudolphi, the shorter head and fins, the peculiarly high neural spines and 

 peculiarities of some of the cervical vertebrae, would seem to distinguish this 

 specifically from the 1 o n g i m a n a, if, as is most probable from the recent 

 researches of Gray, such characters are invariable in the species of Cetaceans. 

 On such premises this animal may be called Megaptera os phy ia. 



A species of this genus has left its remains in the miocene of Eastern Vir- 

 ginia, judging from periotic and other bones sent me by my friend Edw. Hol- 

 way, of Yorktown. Probably it is one of the species described by Leidy, Proc. 

 Acad., 1851, 308. 



A pair of bullae without their other periotic elements has been sent me from 

 the Museum, Salem, Mass., by Frederick W. Putnam, Secretary of the Essex 

 Institute. They-,were presented to the Museum by Capt. J. W. Clever, and 

 are said to have belonged to a hunchbacked whale. Their locality is unknown. 



The transverse section represents a cylinder. Taking the bulla of the left side, 

 the incurved lip of the interior face (position derived from the figures of Balaena 

 australis in Ossemens Fossiles) forming no angle with the inferior aspect : this 

 lip rolls regularly inward without compression or fold ; with its laminae the 

 smooth surface terminates, all the remaining surface of the bulla being closely 

 rugose. Viewed from above, the anterior extremity is more contracted than 

 the posterior, and the outer face presents three inflations, while the inner is 

 medially straight. Of the superoexterior inflations, the middle is prolonged 

 into the usual superior process, which is much recurved, and constricts mode- 

 rately the great fissure at two-fifths its length from its posterior extremity ; it 

 is separated by a deep fissure from the posterior inflation. The main fissure 

 is in one plane, and is expanded into both lips anteriorly. The portion sup- 

 porting the other periotic elements postero-interiorly stands on a strong 

 pedicel. Greatest length, 4 in. 5 1. ; breadth at middle inflations, 2 in. 8'4 1. 



Huxley's figure of the periotic bones of Balaena australis (Elem. Corn- 

 par. Anat. 273) represents the longer process as Cuvier, longer and not so 

 acuminate as in our specimens of the B. cisarctica, but the shorter process 

 as much shorter than in the former figure, and more as in our specimens. 



A pair of earbones of one individual from the Museum Salem, differ con- 

 siderably from those of three individuals of the B. c i s a r c t i c a in the Academy 

 collection of nearly the same size. In them an arched ridge descends from 

 the upper elongate lip process, on its inner side, and, describing a curve, rises 

 to the pedestal of the longer periotic process. In the cisarctica the ridge 

 is inconspicuous, and includes but a groove between it and the labial border, 

 while in the Salem specimen it is very strong, and, descending farther, in- 

 cludes a pocket with the lip border. In the latter there is a broad smooth 

 rim on the rising outer lip margin of the other end ; in the cisarctica none 

 at all. Viewed from below, the end next the long processes is broader and 

 more nearly truncate, owing to the strong development of the exterior inflation 



[Sept. 



