Fauna of the Buda Limestone 
17 
PLEUROPHORIDAE 
Genus ARTICA Schumacher. 
Artica compacta (White). 
PI. VII, figs. 1, 2, 3. 
P achy my a ? compacta White, 1880, Proc. U. S. Nat. Mus., Vol. 
II, p. 297, PI. 6, figs. 3, 4,- (Smithson. Misc. Coll., Vol 19.) 
Pachymya ? compacta White, 1883, Twelfth Ann. Rept. U. S. 
Geol. and Geog. Surv. Terr., Pt. I, pp. 22, 23, PL 17, 
figs. 4a, b. 
Dimensions. — Length, 30mm.; breadth, 19mm.; thickness, 
16mm. 
Original description. — shell small, narrower posteriorly than anteriorly, 
slightly gaping behind; beaks depressed, approximate, incurved, directed for- 
ward., their position being very near the front ; basal margin broadly convex ; 
posterior margin narrowly rounded; postero-dorsal margin forming an oblique 
downward and backward truncation of that part of the shell ; cardinal margin 
nearly straight, subparallel with the basal margin, much shorter than the full 
length of the shell; ligament short, its area depressed and sharply defined; 
front very short, depressed beneath the beaks and narrowly rounded below; 
umbonal ridges prominent and angular or subangular; the space above and 
behind them, moderately broad and flattened ; the remainder of eah valve 
somewhat regularly convex. Hinge and interior markings unknown. Surface 
marked by the ordinary concentric lines of growth. 
A study of the material found in the Buda, shows that this 
shell is not a Pachymya, but either a Trapezium (Cypricardia), 
as White suspected, or an Artica. The material that I have 
been able to study indicates, by its hinge structure, that it be- 
longs to the latter genus. 
Locality. — Shoal Creek, Austin, Texas. 
CRASS ATELLI T I DAE 
Genus STEARNS I A White. 
Stearnsia robinsi White. 
PI. VII, fig. 7. 
Stearnsia robinsi White, 1887, Proc. Acad. Nat. Sci. Phila., Pt. 
1, for 1887, pp. 33, 34, PL 2, figs. 7-9. 
