Gasteropoda of the eocene marls. 235 



extent as above. The position of the extremely narrow slit is marked by 

 an elevated line on each margin. 



This shell differs from L. perlata in the form of the volution, wanting 

 the flattening of the upper surface, and from L. gigantea in its more spread- 

 ing form and greater apical angle. 



Formation and locality : In the upper layers of the Upper Grreen Marls, 

 at Shark River, New Jersey. Collection of the Am. Mus. Nat. Hist. 



TREMATOFUSUS, n. gen. 



Shell short fusiform, with rounded, ventricose body volution, and 

 slender, straight anterior beak and narrow canal, and smooth columella. 

 Volutions ornamented by fine spiral lines, and on the upper part with a 

 series of small tubular nodes, which appear to have formed a series of per- 

 forations around the periphery of the volution similar to those of Polytremaria 

 D'Orb. from the Carboniferous formation. Type T. venustus. 



I propose the above generic name for a species of shell for which I can 

 find no established generic group. The specimens of the only species known 

 are internal casts, and their matrices in green marl; but all the features 

 of the shell are easily obtainable from those in hand. The shell quite 

 closely resembles a high spired form of Polytremaria, provided with a mod- 

 erately long, straight, and slender beak, which in the typical species is about 

 equal to the height of the spire. Except for the perforated nodes or sub- 

 spines, which rise quite abruptly from the body volution, the shell would 

 form a rather short, wide-bodied Fusus, with a rounded and abruptly spread- 

 ing body volution. Of course, as I have only the casts and matrix to judge 

 from, I can not positively affirm that these nodes or spines were really per- 

 forated during life — still they present every reasonable evidence of having 

 been so formed. The shells have been extremely thin in texkire. 



Trematofusus venustus, n. sp. 

 Plate XXXV, Figs. 5-7. 



Shell of moderate size, with an elevated, rather slender spire and very 

 rapidly increasing body volution, and with a slender, straight anterior canal, 

 equaling in length the height of the spire. Upper volutions four in num- 



