8 H NORTH AMERICAN INDEX FOSSILS. 



Pierre of New Mexico, Colorado, Black Hills, etc. 

 665. A. shumardi M. & H. (Fig. 1202.) Cretacic. 



FlG. 1 201. a, Anisomyon borealis, view FlG. 1202. Anisomyon shumardi. 



from .ibove. (After Meek. ) (After Meek.) 



Somewhat smaller and more elongate than preceding, with beak 

 nearer the center. 



Pierre of Missouri River. 



Family Auriculim: Blainville. 



CCVIII. Melampus Montfort. 



Shell ovate-conical, with short, obtuse spire and entire, narrow, 



elongate aperture. Columellar lip with several plications ; outer 



lip sharp, lirate within. Surface smooth. Jurassic (?) -Recent. 



666. M. olivaceus Carpenter. Pliocenic-Recent. 

 Spire conical, barely elevated, of 4-5 flat whorls, slightly angu- 



lated below the shoulder. Columella and inner lip with one strong 

 and several weaker plications; length, 12 mm. 

 Pliocenic-Recent in California. 



CCIX. Rhytophorus Meek. 

 Like Melampus but with shoulder bearing small, rib-like crenu- 

 lations. Columella with two plications ; outer lip smooth within. 

 Cretacic. 



667. R. meeki White. (Fig. 1203, d.) Cretacic. 

 Narrower and more slender than R. priscus with whorls rounded ; 



aperture wider anteriorly. 



