44 GASTEROPODA OF THE INFERIOR OOLITE. 
abundant than at Stoford and Coker. The species of Amberleya, too, are rather 
numerous, and differ somewhat from those of the Sowerbyi-bed; there are also 
species of Onustus allied to O. pyramidatus, Phil., which seem rather peculiar. 
The real “fossil-bed”’ of Bradford Abbas occurs in two blocks. This stone 
when peroxidized is also a yellow ironshot Oolite, but it is much softer and more 
marly than the Paving-stone bed. Hence it is favorable for development, and few 
fossil-bearing rocks in the English Oolites work better. The fossils are in good 
spathic condition for the most part, but there is some variety in this, as also in 
the matrix, due probably to slight differences of position and possibly of horizon. 
As regards the name Sowerbyi-bed, since none but the initiated can pretend to know 
what the ‘true Sowerbyi” is like, it is difficult to say whether it occurs here. 
Mr. 8. 8. Buckman, if I remember rightly, once told me that it was very scarce. 
The most characteristic Ammonites of this bed, and indeed of this horizon through- 
out North Dorset, are those allied to Am. concavus, which we must regard as a near 
relative of Am. Murchison. As far as my experience goes, if the “ true Sowerbyi”’ 
has any resemblance to Sowerby’s figure in the ‘ Mineral Conchology,’ that form is 
far more common in the so-called Sauzei-bed of Oborne than in the so-called 
Sowerbyi-bed of Bradford Abbas. It may be that in that part of Germany whence 
Oppel, and after him Waagen came, the true Sowerbyi is plentiful in the bed that 
bears its name, but such is not the case with us. Now, there can be no doubt, as I 
hope has been already made clear, that the zone in question corresponds to a por- 
tion at least of the Norman “ Maheére ;”’ indeed, this is shown to be the case by 
Waagen himself. Yet I cannot find in the works of M. Eugéne Deslongchamps 
any evidence that the “true Sowerbyi”’ is in any way characteristic of the Norman 
** Mahére,” though Am. concavus is held to be so. As this is the most important 
bed for Gasteropoda hitherto discovered in the English Oolites, there should be as 
little obscurity as possible about its position in the geological scale, and we should 
endeavour, for the Dorsetshire District, to seek our parallels in Normandy rather 
than in Wurtemberg. Since it is recognised as the Sowerbyi-bed, let it be known 
that in this country the recognition can only be granted on the /ucus a non lucendo 
principle, and that the name concavus-bed or beds would with us be far more 
appropriate. 
It may interest some of the readers of the Paleontographical Society to know 
that this remarkable bed, which was sedulously worked for many years by the late 
Professor Buckman, attracted the attention of the late Dr. Wright. In the year 
1856 the results of his impressions on North Dorset were published in the 
‘Quarterly Journal of the Geological Society ’ (vol. xiii, p. 309). Dr. Wright was 
then disposed to correlate the Bradford Abbas fossil-bed with the Frocester 
Cephalopoda-bed, or zone of Am. radians, and he named it the Cephalopoda-bed, 
which for him formed a portion of the Lias. Hence Professor Buckman complained 
