MOORE — ON NKW BUACHIOPODA, ETC. 
439 
At the time referred to but fourteen species, of the genera Lin- 
gula, Orbicuhi, Spirifcr, and Terebratula had been figured from 
the three divisions of the Lias, but I had succeeded in discovering 
twenty new species in the Middle and Upper Lias of Somerset, in- 
cluding the genera Thccidcum, Lcptrona, and Crania, genera which 
had been previously unnoticed in these formations. 
Of the genus Thecideum, the Middle Lias of Somerset yielded me 
three species, \'iz.. T. Ihucliardii, T. triangularis, T. Moorei. In this 
formation they are rai'C, and when found are almost invariably 
attached to the plicated exteriors of Rhynchovella serrata or R. tetrae- 
dra. On a specimen of the former shell, which has been figured by 
Mr. Davidson, there are seventeen examples belonging to the three 
species I have mentioned. 
The Upper Lias of the west of England, especially in the neigh- 
bom-hood of nmiiister, rarely exceeds in thickness ten or twelve feet, 
and is sometimes reduced to foui- or five feet. In the clays at its 
base the genus Leptjena occurs of several species. About the time 
of their discovery, one species, the Leptcena liasiana, had been found 
in France, which I had sought for in vain in this country. During a 
visit paid me by Mr. Davidson, as we were approaching a section of 
Upper Lias, he remarked how interesting it would be to find the 
French species in association ^vith those I had already discovered. To 
our great dehght the first object that presented itself to me was a 
little shell, which rendered the L. liasiana a British species. I have 
never found more than four specimens, so that it is very rare. 
Before the publication of Mr. Davidson's "Appendix," in 1853, I 
had examined the Inferior Oolite of Dundry for Brachiopoda, and 
found there eight species of Thecideum, five of which were new, 
together with the T. Boucharclii and T. triangularis I had previously 
obtained from the Middle Lias,, and T. Deslongcliampsii of the Upper 
Lias. The same locality also furnished me with a series of little 
shells, which threw light upon some I had previously found in the 
Upper Lias, forming a passage between the Thecideidse and the 
TerebratulidiB, for which the sub-genus Zellania has been created. 
These, with a httle shell named Spirifera oolitica, were shortly 
noticed by me in Mr. Davidson's " Appendix," but have since been 
figured and described in the Journal of the Somersetshii-e Natural 
History Society for 1854. At the time of its publication I was con- 
vinced that the discovery of many new species of Brachiopoda might 
be expected from a continued investigation of the secondary forma- 
tions ; and it is to new species found since I now desire to direct 
attention. 
On Hampton Down, near Bath, there are extensive excavatious 
where the Great Oolite was formerly largely worked. Latterly a 
new quany has been commenced, and in order to reach the workable 
beds of freestone, the following beds in descending order had to be 
passed through : — 
