8io CRETACEOUS PALEONTOLOGY. 



size, its stronger revolving markings and in the presence of two 

 columellar folds. 



Pormation and locality. — Merchantville clay-marl, Lenola 

 ( 163) ; Navesink marl ? 



Geographic distribuHon. — New Jersey. 



Avellana costata (Jolmson). 

 Plate XCIX., Pig. 21. 



1898. Cinwlia costata Johns., Ann. Rep. Geol. Surv. N. J., for 



1897, p. 264. 

 1898. Cinidia costata Johns., Proc. Acad. Nat. Sci. Phil, 



(1898), p. 462, text fig. I. 

 1905. Cinidia costata Johns., Proc. Acad. Nat. Sci. PhiL 



(1905), p. 19. 



Description. — ^"Shell with four whorls, spire prominent, body- 

 whorl with from 12 to 13 revolving grooves, which form an 

 equal number of smooth, flat, revolving costse; these average- 

 about double the width of the grooves. In one specimen the 

 third and fourth costas from the suture are about twice as wide 

 as the others, and the two' lower costae are divided by a min- 

 ute, impressed line. The first spiral whorl has six and the sec- 

 ond five revolving grooves. Apical whorl smooth, suture deeply 

 impressed. Aperture narrow, oblique, lip broad, thick and cren- 

 ulated on the inner margin with eight small teeth-like projections,, 

 and extending tO' the suture, where it joins the callus of the peris- 

 tome, which is continuous to the base of the columella; base- 

 with two oblique folds, above which is a prominent fold or plate 

 extending at almost right angles to the columella; between this, 

 and the posterior angle o-f the aperture is a small, tooth-like pro- 

 jection. 



Alt., 4; diam., 2j4 mill." (Johnson.) 



Pormation and locality. — Woodbury clay ?, Deep well at 

 Mount Laurel (Johnson). 



Geographic distribution. — New Jersey. 



