THE GEOLOGIST. 



Ft. 111. 



1. Thin bands of freestone 4 6 



2. BrowTi raggy coralline bed 9 0 



3. Compact grey limestone 5 0 



4. Workable beds of great oolite 20 0 



The grey limestone (No. 3) contains many organic remains, but 

 owing to its hard and intractable character few are to be extracted 

 entire. In its weathered edges may be seen the L{7ua cardtiformis, 

 Triclvites, Litliodomi, and many corals. 



The raggy bed (No. 2) is very incoherent, and appears to have 

 been an ancient coral reef, it being in great part composed of corals 

 and sponges. Intermingled with these branching corals are myriads 

 of beautiful organisms, which, from the unconsolidated nature of the 

 bed, are easily extracted. They consist of dismembered ossicles of 

 starfishes, the plates and occasionally the bodies of the Bradford 

 Encrinite (Aijiocrinus Parkinsoni), s^mes and shells of Echini, Oystroea3, 

 and other moUusca, and with them very many specimens of a small 

 Brachiopod, which has hitherto been considered the young of Tere- 

 hratula maxillata, but which I shall presently show is to be referred 

 to Terebratella. 



The Brachiopods obtained at Hampton consist of Terebratula 

 cardium, T. coardata, T. digona, T. hemispherica, T. maxillata, lihyn- 

 cJionella concimia, R. ohsoleta, Crania antiquior. It will thus be seen 

 that only three genera of Brachiopods have hitherto been known in 

 the Great Oolite, and the bed under consideration. To these I have 

 now to add four other genera, viz., Terebratella, Terebratulina, The- 

 cideum, and Zellania. 



Teeebeatula maxillata. Sow. PI. xiii., figs. 6, 7. 



The adult form of this shell is found at Hampton, though usually 

 either in single valves, or in a crushed state. The young ages of 

 this shell are externally hardly distinguishable from the Terehratella 

 Buchmani, described below. It difiers from the latter shell in its 

 beak being more truncated, and the foramen more rounded ; it is 

 also usually longer than broad, a character it loses when more adult. 

 Internally the generic difference is at once apparent, as this shell 

 possesses a short reflected loop, which in Terebratella is doubly 

 attached. 



Teeebeatula hemisphj^eica. Sow. 



A pretty little shell, originally figured by Sowerby under the name 

 of Terebratula hemisphcerica, is not uncommon at Hampton Clifis. 

 This was subsequently removed by D'Orbigny from that genus, and 

 placed with the Terebratellse ; and on the authority of the species to 

 which I now refer, that author carried the latter genus into the 

 oolites, in which he was followed, although with some hesitation, by 



