SECTION IV. 
EOCENE GASTEROPODA FROM THE UPPER LAYER OF THE UPPER 
MARL BED OF NEW JERSEY. 
Class GASTEROPODA. 
Subclass PROSOBRANCHIATA. 
Order PECTINIBRANCHIATA. 
MURICIDE. 
Genus MUREX Linneus. 
MvuREX (PTERONOTUS) LEVAVARICOSUS, N. Sp. 
Plate xxiv, Figs. 1, 2. 
Shell small, ovate, spire elevated, number of volutions unkown, apical 
angle about 45°. Volutions subglobular between the deeply impressed 
sutures, the body whorl appearing globular when considered alone. Aper- 
ture semicircular, beak long, strongly curved and very slender. Volutions 
crossed by low rounded varices, which in the cast readily slough from the 
surface, showing that the inner layers of the shell were built up independ- 
ently of the exterior form, as the shell was continued beyond the line of the 
varix; lip reflected only in the degree of a varix. Shell marked by fine 
spiral lines, which are more distinctly indicated on the lower side of the 
whorl than above; also by very fine transverse lines indicating growth. 
Only a single individual of this species has been observed, and that 
impertect above the middle of the second volution. The specimen has been 
studied by Mr. Conrad in past years, and marked by him as being nearly 
related to Lusus rugosus Lamarck, as figured by Sowerby. The form of the 
varices, however, and their condition of preservation show that they were 
not formed as are those of Fusus, Fasciolaria, and allied genera, but like those 
of the true Murex. The species is readily distinguished from any known 
form in our American Eocene, and need not be mistaken, 
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