AMMONITES FROM THE INFERIOR OOLITE. 



r>7 



6. On the Terminations of some Ammonites from the Inferior 

 Oolite of Dorset and Somerset. By James Buckman, Esq., 

 E.G.S., E.L.S., &c. (Read June 23, 1880.) 



During the progress through the press of D'Orbiguy s ' Paleonto- 

 logie Erancaise, " Terrains Jurassiques," I was busily engaged in col- 

 lecting the fossils of the Inferior Oolite and Lias in the neighbour- 

 hood of Cheltenham. In both of these rocks I had the good fortune 

 to find a somewhat large series of Ammonites, the greater propor- 

 tion of which I could readily identify from D'Orbigny's figures*. 



But as these fossils were in bad condition, especially when com- 

 pared with the French drawings, I was at first almost led to think 

 that these latter had been somewhat unjustifiably made up or, as 

 we should say in plain English, " fudged." 



Thus, in reckoning up the plates of admitted Inferior Oolite Am- 

 4 monites in the ' Paleontologie Erancaise, ' Yv r e find them to be thirty- 

 eight, out of which no less than twenty species (a little over two 

 thirds of the list) are drawn with the mouth of their shells more 

 or less perfect ; and yet, strange to say, I do not recollect a single 

 example of their Cotteswold prototypes having occurred to me in 

 this perfect condition. 



Since those days of scepticism, however, D'Orbigny's book has 

 become my constant and trusted companion, as the specimens in 

 our Dorsetshire list of Ammonites appear to be in much the same 

 condition as those figured by that talented author. 



During the last seventeen years my lot has been cast in the 

 pleasant county of Dorset ; and, curiously enough, the farm that I 

 have occupied is situate on the Inferior Oolite ; the Halfway-house 

 quarry is within a mile of my own residence ; whilst a quarry in 

 one of my own fields, within a hundred yards of my house, has 

 proved to be one of the richest in England, if not in the world, in 

 Oolitic fossils, and especially in the species of the Cephalopoda 

 and Gasteropoda, in each of which great classes we may safely 

 reckon as many as from sixty to seventy species. From this quarry 

 and the surrounding district, there have been determined as many 

 as twenty-eight species of Brachiopoda ; and I probably possess 

 nearly, if not quite, a hundred forms of Lamellibranchiata, which, 

 not to name other remains, cannot but be considered as a goodly 

 list. 



If, again, we consider that the greater part of the individuals of 

 these lists occur in a bed varying from 2 to 3 feet in thickness, 

 the surprise becomes still greater ; and not only are the species so 

 numerous, but it is one mass of specimens, as, instead of our merely 

 finding an Ammonite here and there (as in the Cotteswolcls), this par- 

 ticular bed is a mass of them, so that several species will be huddled 

 together in a small space ; and, in so far as the Ammonites are 

 * The part, on the ' : Ceplialopodes " was finished in 1849. 



