LAMELLIBRANCHIATA. 501 



Glossites patulus, n. sp. 



PLATE XCVI, FIGS. 15, 16. 



Shell of medium size or larger ; length less than twice the height ; basal mar- 

 gin gently curved posteriorly, becoming nearly straight anterior to the mid- 

 dle. Posterior extremity abruptly rounded below, and obliquely sub-truncate 

 above. Cardinal line depressed, oblique, and gently arcuate. Anterior end 

 obliquely truncated by the lunule and narrowly rounded below. 



Valves depressed-convex in the lower and posterior portions, becoming 

 moderately convex in the umbonal region. 



Beaks at the anterior fourth or fifth, small and closely appressed. Umbo- 

 nal slope convex above, becoming depressed toward the post-inferior 

 extremity. 



Surface marked by fine striae of growth, which are fascicled and produce 

 concentric undulations on the body of the shell. Anterior muscular scar 

 moderately impressed, situated just within the anterior border below the 

 lunule. 



Four specimens measure respectively 28, 36, 45 and 50 mm. in length, and 

 17, 20, 25 and 28 mm. in height. 



This species is distinguished by its broad, flattened form, in which characters 

 it diflers from any other species of the genus noticed in this volume. 



Formation and localities. In the Chemung group, at Rockville, N. Y., and 

 Mansfield, Pa. 



Glossites amygdalinus. 



PLATE XL, FIGS. 13, U. 



SanguinulUes aiaygdalinus, Winchell. Proc. Acad. Nat. Sci., Phila., p. 13. 1863. 



In part Modionuyrpha f amygdalina (Winchell), Hall. Prelim. Notice Laraellibranchiata, 2, p. 78. 1870. 

 •• " " " " Pal. N. Y., vol. V, pt. 1. Plates and Explana- 



tions : PI. 40, figs. 12-20. 1883. 



Shell below the medium size, sub-elliptical ; length a little more than twice the 

 height. Basal margin gently curved, abruptly rounded into both extremi- 

 64 



