MYALINA. 
47 
Myalina peralata^ de Koninck,^ is much more triangular in shape, and has a 
slightly more definite anterior wing. 
2. Myalina Damnoniensis, Phillips, sp. PI. Ill, fig. 6. 
1841. MiTiLTJs Damnoniehsis, Phillies. Pal. Foss., p. 37, pi. xvii, fig. 61. 
1854. — ? — Morris. Catal. Brit. Foss., p. 214. 
1889. — — Mheridge. Foss. Brit,, vol. i, Pal., p. 161. 
? 1891. Mtalima BEUSHArsEKi, Freeh. Abbandl. Geol. Specialk. Preuss., Band ix, 
pt. 3, p. 145, pi. xvi, figs. 16, 16«. 
Bescri/ption. — Shell ovoid, short, very high, convex, moderately large. Umbo 
anterior, prominent, proximate. Hinge-margin straight. Anterior margin very 
broad, straight. Inferior and posterior margins convex. Hind wing produced, 
defined, and flat. Line of greatest elevation near, and parallel to, the anterior 
side, over which the shell is gently convex, gradually becoming less so behind, 
and being very steep in front near the margin. 
Size. — The specimens are too imperfect for measurement. 
Locality. — Wolborough. Phillips's type and a second, but doubtful, specimen 
are in the Museum of Practical Geology. 
EemarliS. — From the accidental marks there can be no doubt that the shell in 
the Museum of Practical Geology is the specimen which Phillips has figured, 
though his figure does not accurately represent it, but presents the appearance of 
a longer and flatter shell. It is so defective as to give very few specific 
characters, and on that account Phillips himself only named it provisionally. On 
the other hand, he has laid stress upon the defined flattened hind wing, which 
clearly distinguishes it from the other species described from these beds. The 
second specimen in the museum is still more defective, and can only be doubtfully 
referred to the same species. 
M. Beusliauseni, Freeh, seems to correspond almost exactly in shape. It has, 
however, a delicate surface ornamentation, which Phillips's specimen, perhaps 
from its state of preservation, does not show. 
Affinities. — From Myalina egregia it difiers by the definite angle which marks 
off the hind wing, by its much less recurved umbo, by its more evenly convex 
back, and probably by its greater width in the inferior regions. 
Avicula ohsoleta, Goldfuss,'^ seems to present a somewhat similar appearance in 
the relations of the wing to the rest of the shell. It is, however, much more 
transverse, and its umbo is less anterior. 
1 1885, de Koninck, 'Ann. Mus. Eoy. H. N. Belg.,' vol. ix, pt. 5, p. 172, pi. xxix, fig. 5. 
2 1 834-40, Goldfuss, ' Petref. Germ.,' vol. ii, p. 125, pi. cxvi, figs, la, b. 
