BRACHIOPODA. 
9 
The retention, in the fossil state, of the pedicle, is a rare occurrence. ~ Of 
palaeozoic species, Mr. Davidson^ has figured 
an example of L. ? Lesueuri, in which the 
impression of this organ is very distinctly 
shown. More recently, Mr. Walcott f has 
described a beautiful example of L . aqualis, 
Hall, in which the narrow arm is seen pro¬ 
truding from the aperture in the cardinal 
area. By the favor of Dr. J. S. Newberry, 
we have been allowed to figure a specimen 
from the Waverly sandstone at Oil City, 
Penna. (see Plate IY k, fig. 7), in which the 
pedicle is also distinctly visible. The species 
is the one identified as L. Scotica, Davidson, 
by the Ohio geologists, and more recently described by Mr. Herrick^: as L. 
Waverliensis. 
In regard to the myology of the palaeozoic Lingulas, we have satisfactory 
evidence that the arrangement of the muscles did not differ widely from that 
in recent members of the genus. It is, however, not often that a palaeozoic 
specimen is found which has retained upon the surface of the shell, or left upon 
the matrix, traces of the delicate muscular scars; and in such instances usually 
only the stronger impressions are discernible. A few examples have been figured 
by recent American writers, which retain, in exquisite detail, not only the mus¬ 
cular, but also the pallial impressions of the shell. Of these, one is a brachial 
valve of the L. Whitii, of Walcott, figured in his Palaeontology of the Eureka 
District ;§ another, an internal cast, representing the impressions on both dorsal 
and ventral valves of L. JElderi, Whitfield, figured by the author first, in the Amer¬ 
ican Journal of Science,|| and subsequently; in the Report of the Geological Survey 
* Brachiopoda of the Budleigh-Salterton Pebble-bed, p. 362, pi. xl, fig. 16. 
f Proceedings of the United States National Museum, for 1888, p. 480, fig. 3. 
J Bull. Denison Univ., vol. iv, pt. 1, p. 18, pi. iii, fig. 1. 1888. 
§ Page 109, pi. xiii, fig. 3, and pi. xxi, fig. 19. 1884. 
| Vol. xix, p. 473. 1S80. 
Pig. 4. Fig. 5. 
Lingulacequalis , Hall. Lingula ? Lesueuri , Rouault. 
With pedicle. With pedicle. 
After Walcott. After Davidson. 
