MARYLAND GEOLOGICAL SURVEY 699 



lateral very distinct pits, the posterior one very distant from the apex. 

 The pallial sinus is rounded and extends to a direct line between the apex 

 and ventral margin, according to d'Orbigny's figure 5, and beyond that 

 point in figure 17. The present species approaches figure 5 most nearly 

 in outline, but the radiating lines over the whole disk is a distinguishing 

 character, and the height of the shell is proportionally less." Conrad, 

 1870. 1 



The shell is rather small, equivalved and subequilateral, moderately 

 heavy, more or less elongated transversely, with well-rounded lateral 

 margins. The characteristic sculpture is a radial lineation with inter- 

 secting concentric strise. The genus is restricted in its known distribution 

 to the Cretaceous. 



LlNEARJA METASTRIATA Conrad 



Linearia metastriata Conrad, 1860, Jour. Acad. Nat. Sci., Phila., 2d ser., 



vol. iv, p. 279, pi. xlvi, fig. 7. 

 Linearia metastriata Meek, 1864, Check List Inv. Fossils, N. A., Cret. and 



Jur., p. 14. 

 Linearia metastriata Conrad, 1870, Am. Jour. Conch., vol. vi, p. 73, pi. iii, 



fig. 11. 

 Linearia metastriata Whitfield, 1885, Mon. U. S. Geol. Survey, vol. ix, p. 



165, pi. xxiii, figs. 6, 7. 



Linearia metastriata Johnson, 1905, Proc. Acad. Nat. Sci., Phila., p. 16. 

 Linearia metastriata Weller, 1907, Geol. Survey of New Jersey, Pal., vol. 



iv, p. 618, pi. Ixx, figs. 8, 9. 



Description. " Oblong-oval, convex, subequilateral ; posterior end sub- 

 truncated ; disk with fine concentric lines and distinct radiating lines 

 anteriorly, and larger crenulated radii posteriorly ; the rest of the surface 

 with microscopic radiating lines; cardinal tooth under the apex widely 

 bifid; lobes small and slender." Conrad, 1860. 



Type Locality. Eufaula, Alabama. 



Shell transversely oval in outline; anterior end evenly rounded, pos- 

 terior obscurely truncate; external surface very finely cancellated, con- 

 centric sculpture of fifty to sixty acute lirations, which evenly override the 

 radials in the medial portion of the disk but are minutely undulated by 



'Am. Jour. Conch., vol. vi, 1870, p. 73. 

 46 



