CARBONICOLA AQUILINA. 73 
February 5th, 1834, and on April 13th and 27th, 1836. The Assistant-Secretary, 
Mr. L. Belinfante, B.Sc., has kindly looked up the original minutes of these 
Meetings, and he finds with regard to the Meeting on February 5th, 1834, the 
following entry :—‘‘ The author concludes his memoir with some observations on 
the fossils . . . of 18 generaof shells which he enumerates; 12 are marine.” 
In the minute for April 27th, 1836, is found—* The fossils of the coal-measures 
are described with great detail.” This evidence I take to be conclusive as to the 
priority of the name aquilina over atrata. I endeavoured to obtain accurate 
information as to the character of Goldfuss’s shells, but Professor Schliiter of 
Bonn, where the originals are said to have been placed, writes me that they have 
either disappeared or are so fragmentary as to be unrecognisable. 
I have come to the conclusion that the shell figured by Sowerby as Unio 
phaseolus is only a very young form of C. aquilina. The original figure agrees 
very closely with the shell figured on Pl. X, 19 to 42, a series of casts intended 
to show stages of growth, from the roof of the Hard Mine seam, North Stafford- 
shire, in which bed the shell occurs in hundreds, the majority of the specimens 
being casts of perfect examples. Its anterior end is shown to be very small in 
the original figure, a condition which is shown specially in Pl. X, figs. 26, 33, 40. 
There can be, I think, little or no hesitation in referring Captain Brown’s three 
species, Pachyodon or Unio lateralis, bipennis, and sulcatus, to C. aquilina. The 
figures of Pachyodon and Unio lateralis are those of a cast which shows the 
characteristically shaped anterior end, and are closely resembled by Pl. X, fig. 36. 
The figures of Pachyodon and Unio sulcatus show the obliquity of the lines of 
growth and anteriorly directed umbones, and agree in general shape with the 
deeper forms of C. aquilina, Pl. X, figs. 15, 16, 17, and 20, from Whitley; but the 
figures of Pachyodon and Unio bipennis have the characteristic features of 
C. aquilina, and evidently belong to that form which possesses a blunt truncated 
posterior end, as Pl. IX, figs. 2, 3, and 31; PI. X, figs. 20 and 23. 
Professor King says, in his remarks on his new species Anthracosia Beaniana, 
“This species has some resemblance to Brown’s Pachyodon bipennis, but it differs 
from the latter notably in the anterior end being much shorter,” a character 
which a study of my figures on Pls. [IX and X will show not to be of specific value. 
The description is very meagre, consisting of “* Diagnosis: Oval, very inequilateral. 
Umbones small; valves thin, rather tumid, and marked with nearly obsolete 
wrinkles,” which, unfortunately, gives no very definite characteristics. Figures 
only of the inner surface of the shell are given; but in these the obliquity of the 
lines of growth curving over the posterior slope into the groove along the edge of 
the valve are markedly shown. The originals cannot be traced, unless some 
fragments in the Science Museum, Newcastle-on-Tyne, which Mr. Howse tells me 
are labelled in Professor King’s handwriting, represent them. One of these 
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