58 
PALAEONTOLOGY OF NEW YORK. 
Obolella and Lingulella, Ford), which show a close agreement in the internal 
characters of these species. 
In the pedicle-valve the lateral scars make the long sweeping curves so 
characteristic of Obolella, while the centrals, more or less coalesced, produce a 
broad, somewhat tripartite scar. In ^ 
the brachial valve of L Ella , appear Jwlk 
to be two diverging lateral spars, ex- «|jjj§11 f| |f§ !\i 
tending about one-half the length of the 
shell, and incurving at their anterior TAnguuiia ma, Haii^iid whitaeid. 
ends toward the more conspicuous and 
apparently compound central scar. Essentially the same characters are seen in 
the brachial valve of L. codata, accompanied by posterior lateral scars, which 
occupy a position homologous with the terminal scars in the Trimerellids. An 
additional character is given to the muscular scars of the brachial valve in Mr. 
Walcott’s figures of his species, Lingulella Granvillensis * * * § in which there 
appears, near the center of the shell, a faintly defined, bilobed scar, continued 
anteriorly into an oval impression. These represent the “ anterior adductor 
muscular scars, and also what may have been the adjustor muscular scars ”f 
or the anterior laterals and the centrals of Lingula. This feature constitutes 
a conspicuous difference from the obolelloid character of these impressions 
in the brachial valves of the other species cited, and it will be important 
to verify the character. The pedicle-valve of this species shows the straight (?) 
diverging ridges similar to those in L. Dawsoni.% 
Figures have been given by Mr. Davidson, showing the muscular scars in the 
species L. ferruginea, Salter,§. and L. lepis, Salter.|| In both these species the 
elongate, more or less curved laterals are apparent, enclosing a compound central 
scar not essentially differing from that in L. Ella , though more sharply outlined. 
* American Journal of Science, vol. xxxiv, p. 188, pi. i, fig. 15 a. 1S87. 
f Walcott, loc. cit. 
I By the favor of Mr. G. F. Matthew we are enabled to give an original figure of the interior of this 
species taken from the specimen represented in his “Illustrations of the Fauna, of the Saint John Group,” 
No. 3, pi. v, fig. 9 d (Trans. Roy. Soc. Canada, Sec. iv. 1885). We have not observed the sharply defined 
muscular impressions represented by Mr. Matthew. 
§ Mon. Brit. Sil. Brach., pi. xlix, figs. 33a, 35a. 1871; and Geol. Mag., vol. v, No. 7, pi. xv, fig. 3a. 1868. 
|| Mon. Brit. Sil. Brach., pi. xlix, fig-. 31a. 1871; and Geol. Mag., vol. v, No. 7, pi. xv, figs. 11 and 11a. 1868. 
