NORTH-CAROLINA GEOLOGICAL SURVEY. 203.. 



possible hereafter to determine to which ear-bone belonged 

 to the Murfreesborough species. It is evident that neither of 

 these belonged to Prof. Leidy's Orycterocetus, because this 

 belonged to a different family of the cetaceans. 



OTOLITES, OR THE EAR BONES OF WHALES. 



The remains of the cetacea may be said to be numerous in 

 the miocene of North-Carolina. Vertebra and ribs are more 

 commonly found than other parts for the reason that the in- 

 dividual parts exceed in number the other parts of the 

 skeleton. The ear bones are the least common. Of this part 

 I have those which I regard as having belonged to at least 

 three different species. I base this conclusion on the estab- 

 lished fact that these bones possess for each species a peculiar 

 configuration ; that though the bone in question has a general 

 resemblance in all the species of which the family is com- 

 posed, yet in the minute details of construction and form, 

 each species has its own, which may be determined by close 

 and careful comparisons. Thus, in the true whales, the thick 

 posterior part is simple, while in the cachalot it is bilobed, 

 and that this thickened and convex part in the simple kinds, 

 while it is variable in form and extent in the different species 

 of the true whales, and which is also joined to certain other 

 differences, which may be observed in the thin overarching 

 and expanded part. 



For convenience of description, these bones may be divid- 

 ed, longitudinally, into two principal parts: 1. The thick 

 involuted convex part which occupies the posterior segment 

 of the bone, and which extends back to a rough longitudinal 

 surface ; and, 2d. The thinner and expanded part which begins 

 where the former ends, and arches over the first in different 

 degrees, forming, posteriority, a convex surface, and interi- 

 orly towards the first part a concavity differing both in de- 

 gree and extent in different species. The anterior or eustach- 

 ian portion is formed wholly of the thinner expanded part. 

 There is in the form of the expanded part some resemblance 

 to the rim of the human ear. 



The ear bones, in consequence of the thick convex part 



