Morgan Expeditions. 124 
This form of “Modiomorpha, which is quite abundant at 
Ereré, although very constant in its outline, varies consid- 
erably in its surface characters, as described above. The 
specimens obtained are all moulds of the interior and ex- 
terior. Associated with Wuculites Nyssa, Spirifera Pedro- 
ana, ete., in the Devonian sandstone of Ereré, Prov. of 
Para, Brazil. 
Named in honor of Senhor Pimenta Bueno of Para, to 
whom the expeditions are under obligations. 
Genus PALANEILO, Hall. 
Palzaneilo sulcata, sp. nov. 
Shell of moderate size, elongate, slightly gibbous, and apparently sub- 
elliptical in outline, with the height less than two-thirds the length. 
Dorsal margin inclining slightly downward in extending backward from the 
beaks. The anterior margin appears to be slightly concave, for about one- 
third its length from the beaks, and forms an angle of nearly 120° with 
the dorsal margin; in its lower two-thirds it is well and regularly 
rounded. Ventral margin nearly straight and suddenly indented toward 
the posterior extremity of the shell, which is imperfect in all the speci- 
mens of this species yet obtained. Beaks situated at a distance from the 
front, equal to a little less than half the height of the shell. quite pom-- 
inent and incurved to the hinge line. The valves are most convex just 
above and anterior to the middle, with the surface arching quite strongly 
and regularly, the curvature, however, increasing somewhat in strength, 
from the ventral margin to the beaks. A rather deep and well marked 
sinus commences in each valve on the posterior side of the beak, where 
it is very small, and extends obliquely across the valve to the ventral 
margin, near the posterior extremity of the shell, increasing gradually in 
size at the same time, the margin being deeply indented by it. The an- 
terior edge of the sinus is quite abrupt and forms a slight fold on the 
surface of the valve; it makes an angle of about 30° with the dorsal 
margin of the shell; the posterior edge rounds over gradually. From 
the anterior margin of the valve the surface rounds up gradually for a 
short distance, and then extends with very little curvature to the sinus. 
Surface of mould smooth. Length, about 17™™; height, 11°5™™; depth 
of each valve, 3:5 ™™, 
This species of lamellibranch has the external characters 
of the genus Paleaneilo, but the specimens representing it 
are not in a condition to show the character of the hinge, 
