364 CRETACEOUS. PALEONTOLOGY. 



Sub-family MAGELLANINAE. 



Genus TerEbrate^lla d'Orbigny. 



Terebratella plicata (Say). 



Plate XX VII., Figs. i-ii. 



1820. Terebratula plicata Say, Am. Jour. Sci. ist ser., vol. 2, 



P- 43- 

 1829. Terebratula plicata Say, Jour. Acad. Nat. Sci. Phil., ist 



ser., vol. 6, p. 73, pi. 3, figs. 5-6. 

 1834. Terebratula Sayi Mort., Synop. Org. Rem. Cret. Gr. 



U. S., p. 71, pi. 3, figs. 3-4. 

 1845. Terebratula Sayi Mort., Am. Jour. Sci. ist ser., vol. 48, 



p. 283. 

 1861. Terebratella plicata Gabb, Synop. Moll. Cret. Form., p. 



249 (193)- 

 1864. Terebratella plicata Meek, Check List Inv. Foss. N. A., 



Cret and Jur., p. 5. 

 1868. Terebratella plicata Con., Cook's Geol. N. J., p. 375, 



figure; p. 723. 

 1870. Terebratella plicata Credner, Zeitsch. d. Deutsch. Geol. 



Gessell., vol. 22, p. 224. 

 1886. Terebratella plicata Whitf., Pal. N. J., vol. i (Monog. 



U. S. G. S., vol. 9), p. 12, pi. I, figs. 5-9. 

 1905. Terebratella plicata Johns., Proc. Acad. Nat. Sci. Phil., 



1905, p. 6. 



Description. — Shell subcircular or subovate in outline, pointed 

 posteriorly and rounded in front, strongly plicated, each valve 

 marked by from 8 to 12 or more sharply angular plications 

 which extend to the beak; usually a little wider than long 

 but sometimes longer than wide; the dimensions of four speci- 

 mens are: length, 14.5 mm., 15.5 mm., 19 mm., 17.5 mm.; 

 width, 16 mm., 15 mm., 20 mm., 16.3 mm.; thickness, 8 mm., 

 9 mm., 10 mm., 9.5 mm. Pedicle valve strongly convex, with 

 a small, nearly erect beak ; cardinal area of moderate size, sharply 

 defined, slightly concave, with a broad delthyrium partially closed 



