128 PALEONTOLOCJY OF NEW JBKSEY. 



Amoug the examples wliicli I have seen of this species there is but 

 little variation except in size, and not much in this respect among the adult 

 specimens. It is very readily distinguished from the other naticoid shells 

 of New Jersey, except N. ahijssina Morton, by its oblique patulose form, and 

 from that one by its smaller size and by the flattened space below the suture, 

 which is a very distinctive feature as compared Avith any of the associated 

 species. The broad, open umbilical cavity which appears to have been en- 

 tirely destitute of callus or thickening of any kind, or even of reflection of 

 the columella, and with a somewhat angular margin, will also be a distinctive 

 mark. Externally it has some resemblance to Gyrodes Alahamiensis Whitf , 

 from the Eocene,^ but is more oblique and not so elevated; but in the um- 

 bilical area it is entirely different. Perfect shells from Texas show the sur- 

 face to be marked only by fine concentric lines of growth. G. alveata Con- 

 rad^ appears to be the same species, and the figure given a very good one. 



Formation and locality: Dr. Morton's type specimens were from Prairie 

 Bluff, Alabama, where it is not unconunon. All the New Jersey specimens 

 yet seen are either from Mullica Hill, near Mount Holly, or Crosswicks 

 Creek. It also occurs in many ulaces in Alabama, and in a very perfect con- 

 dition in Texas. 



Gyrodes altispira. 



Plate XVI, Figs. 7, 8. 



Lunatia ? altispira Gabb: Proc. Acad. Nat. Sci. , , PMla. , 1861, p. 330; Meek, 



Check List Cret. and Jur. Foss. , p. 20. 

 Lunatia altispira (Gabb) Meek: Geol. N. J., Newark, 1868, p. 739. 



The internal casts which I have placed under this species are about 

 three-fourths of an inch in height, and about half an inch in diameter on the 

 body whorl; the form is erect and the spire elevated, with about three and 

 a half volutions, the last one forming, two-thirds of the entire height, and 

 by much the greatest bulk of the shell; summit of the body volution 

 squarely truncate or flattened adjacent to the suture, and a little flattened 

 below, thus forming a rather distinct angle on the top of the volution; the 

 umbilicus is small, but open, and withou,t thickening or callus; base of the 



' Am. Jour. Couch., vol. 1, p. 263, PI. xxvii, Figa. 9, 10. 



2 Jour. Acad. Nat. Sci., Phila., 2d ser., vol. 4, p. 289, PI. xlvi, Fig. 45. 



