EDMONDIA. 
8 
indistinct, irregular, and unequal striae or growth-lines. Hinge invisible. Shell- 
structure extremely thin. 
Size of right valve. — Length 40 mm., breadth 20 mm., depth 8 mm. 
Locality. — There is a specimen in Mr. Vicary's Collection from Wolborough. 
Remarks. — The fossil here described is imperfect in front, and presents few 
data for determining its position. A comparison, however, with the numerous 
Carboniferous species of Edmondia, described by de Koninck, shows that, as far as 
can be judged from outward characters, it evidently belongs to that genus. Its 
much greater length distinguishes it specifically from all of them except E. ? debilis, 
de Koninck,^ E. ? praelonga, de Koninck,^ i?. elegantula, de Koninck,' and E. ? angusta, 
de Koninck;* each of which differs from it by being much broader in front and 
narrower behind. 
2. Edmondia, sp. 
Description. — Right valve long, ovoid, tumid, the length being to the height 
as 3 : 2o Umbo apparently anterior, rounded, rather prominent. Area broad, 
concave, indefinite. Anterior margin probably rather broad. Inferior margin 
very slightly convex. Posterior margin roundly convex. Dorsal margin pro- 
bably straight near the beak, and then becoming slightly oblique and convex. 
Contour of back very much rounded, with steep sides except posteriorly. Surface 
covered by fine, indistinct, irregular, and unequal striae or growth-lines. Hinge 
invisible. Shell-structure extremely thin. 
8ize of right valve. — About 41 mm. in length, 28 mm. in breadth, and 10 in 
depth. 
Locality. — A single defective specimen from Wolborough is in the Museum of 
Practical Geology. 
Bemarks. — This specimen is very poor and fragmentary. At first I supposed 
it to be a second example of E. coelata, but further examination makes me believe 
that it is really distinct from that species. The chief difference lies in its general 
shape, which is much less transverse, and considerably less tumid. While in the 
former the length is double the height, in the present form their ratio is only 
3 : 2. The umbo also seems less transverse, and the area broader, shallower, and 
more diffuse behind. It is too defective to admit of being figured. 
1 1885, de Koninck, ' Ann. Mus. Koy. H. N. Belg..' vol. ix, pt. 5, p. 50, pi. vii, figs. 17, IS. 
2 Ibid., p. 50, pi. vii, figs. 21, 22. 
3 Ibid., p. 45, pi. xi, figs. 17—19. 
* Ibid., p. 50, pi. xiii, figs. 6, 7. 
