674 CRETACEOUS PALEONTOLOGY. 



Remarks. This is the species of Scala which has been most 

 commonly met with in the recent collections of the Survey, but it 

 is always a rare shell. The specimens are either internal casts, 

 or the shell substance is very imperfectly preserved, the vertical 

 folds of the shell usually adhering closely to the matrix. 



Formation and locality. Merchantville clay-marl, Lenola 

 (163); Marshalltown clay-marl, near Swedesboro (177); 

 Wenonah sand, near Crawfords Corner (i26 3 ), near Marlboro 

 (130); Navesink marl, near Crawfords Corner ( 1 26 7 ); Red 

 Bank sand, Red Bank (116) ; Tinton beds, near Freehold (132), 

 Geographic distribution. New Jersey, Alabama. 



Scala thomasi Gabb ? 

 Plate LXXVL, Fig. 4. 



1876. Scala (O polio) Thomasi Gabb, Proc. Acad. Nat. ScL 



Phil. (1876), p. 296. 

 1892. Scalaria (0 polio-) Thomasi ? Whitf., Pal. N. J., vol. 2 



Monog. U. S. G. S., vol. 18), p. 137, pi. 18, fig. i. 

 1905. Scala thomasi Johns., Proc. Acad. Nat. Sci. Phil. (1905),. 



p. 20. 



Description. "Shell slender, turreted, whorls numerous,, 

 closely coiled and very ventricose, with rather close sutures, num- 

 bering seven or more in a specimen of less than seven-eighths of 

 an inch in length ; apical angle less than 30, probably not more 

 than 25, the specimen being too imperfect to allow of positive 

 measurement; aperture apparently round and the base of the 

 volution slightly carinate, and the axis imperforate; surface 

 marked by numerous slender, longitudinal ribs or varices, which 

 are erect, closely arranged, and directed obliquely backward in 

 passing from the upper to the lower side of the volutions ; minute 

 surface structure not visible on the specimen in hand." (Whit- 

 field.) 



Remarks. This species has not been met with in the recent 

 collections of the Survey, and the original reference of the species 

 is too indefinite to allow its proper geologic horizon to be cor- 



