82 MALONE JURASSIC FORMATION OF TEXAS. Lbull. 1 
Pholadomya pr^eposita sp. 11. 
PI. XVI, tigs. 3, 4. 
Shell small for its genus, cuneate-oblong. arched somewhat dow 
ward, very broad across the antero-dorsal or umbonal region, t 
breadth at least equal to the height, convex-cuneately narrow 
toward the base and rear; anterior side rather truncate; base gent 
convex; beaks anterior, terminal, projecting forward a little beyo: i 
the rest of the shell, directed forward and upward, then arch 
strongly inward, the apices curved a little backward, somewhat coi 
pressed as if by gentle pressure on the anterior (or inferior) and p< 
terior (superior) sides; surface with faint concentric markings ai 
several remote, low, slender, carinii'orm costelhe which radiate frc 
the summit of the beaks, the anterior 6 (or more) obliquely crossi: 
the inferior (anterior) umbonal slope to the base. The anterior m 
of the base is sharply and even a little biconcavely compressed, and 
limited anterior region of the shell is free from the cariniform ra; 
Measurements. — Height, 22 mm.; breadth, 22.5 mm. In a secoi 
specimen, height, 20 mm.; breadth, 20 mm. The length of the 
specimens (at least more than 31 mm.) can not be exactly given, 
they are posteriorly broken off. A third, with only remnants of t 
shell, but nearly normal as to shape, gives, height, 20 mm.; breadt 
20 mm.; length, 34 mm. A fourth example, too much weathered I 
the flanks to give the breadth, has a height of 24 mm., and a lenj 
of 43 mm. 
Occurrence. — Four examples from locality \\ miles east of Malo 
station. 
Genus PLEUROMYA Agassiz. 
Pleuromya lnconstans C. and A. 
PI. XVII, figs. 1-5; PI. XVIII, figs. 1-3. 
Pleuromya inconstans Castillo and Aguilera, 1895, Bol. Com. Geol. Me 
No. 1, p. 10, PI. V. figs. 15, 16, and PI. VI. figs. 1 to 4. 
Pleuromya inconstans Cragin, 1897, Jour. Geol., vol. 5, p. 817, footnote, m 
p. 819. 
Though outnumbered at many points by its associates, this is t 
most generally distributed fossil of the Malone formation. It rang 
through the entire Theta subdivision of the Malone hills (Tri 
section, or so much of it as is exposed at the locality 1| miles east 
Malone station, whence several hundred specimens were obtain! 
Tt was also collected by me in the lower part of limestones overly ii 
conglomerate in the anticline at the eastern base of Malone Mounts! 
about 1 mile from the southern end, and was, I believe, found 
poorly preserved examples in the gap west of the Trio, with Trigcm 
