208 NORTH-CAROLINA GEOLOGICAL SURVEY. 



thin involuted expansive is arched so as to have a distance of 

 only half an inch from the thick involuted part. This may be 

 divided into three principal lobes; two of them make up two- 

 thirds of thin part, and these are divided externally by a deep 

 sulcus, and internally by a thick rounded ridge which extends 

 nearly to the base ; the lobe of the thickest end is short. A 

 deep sulcated cavity is formed by the thick and thin involu 

 ted parts of the bone. This cavity is 3 inches and six-tenths 

 long and 2 inches and one-tenth, and the height nearly 3 

 inches. 



An ear bone having the form and proportions of the Balaena 

 Mysticetus, in many particulars, I have obtained from Craven 

 county. The most important difference is in the height of 

 the thick involuted part, the thin expanded part is broken off 

 but there are so many points of resemblance, that it is highly 

 probable it belonged to this species of whale. The fossil ear- 

 bone is smaller. Its greatest length is only 4 inches and 2 

 tenths, and the height of the thick involuted part is only 2 

 inches and 2 tenths. Still, it is not at all improbable that we 

 may regard it as having belonged to the young of the B. mys- 

 ticetus, and if so this species commenced its existence in the 

 Miocene period. This conclusion is founded upon the proba 

 bility, that this ear-bone and certain thick heavy ribs of a whale, 

 often found in the miocene deposits, belonged to this species. 

 It is probable, too, that ear-bones vary somewhat in form and 

 thickness in the same species ; this is certainly true in the 

 case of the ear-bone of h shes, of which I have many speci 

 mens, among which there are several varieties of form and size. 

 Other forms of cetacean ear-bones occur abundantly in the 

 raiocene of Tar River. Figure 28 belongs to one of the rarer 

 forms of ear-bones. It has a distinct in 

 voluted portion. It is figured of the natu 

 ral size. 



Figure 29 is another form of ear bone 

 which is the most common of all, except 

 the following. It has no distinct invo- 



