744 PROF. REYNOLDS AND MR. VAUGHAN ON THE [ Nov. 1902, 
Of the paleontology of the lower beds we have no record, for 
the rock-specimens from the shafts contain no fossils. But from the 
upper beds, which are exposed in the cutting to the east of the tunnel- 
mouth, we have obtained an extensive series of fossils. These have 
been collected at different times during the making of the cutting, 
so that the section has been examined almost bed by bed. Again, 
the dip, which is variable both in direction and amount (a south- 
easterly dip of 7°5° was measured at one point), has always an 
easterly direction, and brings each bed in succession down to the 
floor of the cutting, so that it can be easily examined. 
The following is a detailed account of the section taken near the 
mouth of the tunnel, but generalized, so as to apply, with more or 
less accuracy, to the whole expanse of Great Oolite. 
(i) Lithology of the Section immediately East of the 
Tunnel. 
eo Thickness in feet. 
BS { Thick shales or clays containing two or more separated 
ee bands of limestone, which jut out like parallel ledges...... 
— 
({ F. A thick mass of limestones, false-bedded, wedge- | AB 
bedded, and much jointed, with occasional lenti- 15 
| cular bands of dark clay. J : 
| E (2). Sandy layer, thickest just at the mouth of the )\ 
ea tunnel, but thinning out rapidly eastward; it can, | 
a however, be traced, though much attenuated, to | b 
S . yar acta about 
oro the point at which it disappears below the floor 6 
e | of the cutting. \ Grlere 
= 4 (1). Lenticular band of dark clay; this is about 4 feet | je 4) 
fs = te Rae BE ts ickest ). 
on thick at the tunnel, but thins out very rapidly 
= eastward and dies out entirely before reaching the 
= | floor of the cutting. | 
Sia: A thick mass of limestone, false-bedded, wedge- 
| bedded, and much jointed, with occasional lenti- awoue 
: cular bands of sand and dark clay. On, 
| This group rests upon a more or less persistent ss 
thin sandy layer. 
= jot Massive, fine-grained, white oolitic limestone (un- 
=o fossiliferous) ........... witb cadneoDdbLe conse eee eee 3 
oH | B. Lenticular band of black clay, passing laterally into | Ba 
Ox sand, but ultimately merging into the general 1 
Ste | limestone-mass. } ae 
Saeko: Massive, fine-grained, white oolitic limestone (un- 
o | fossiitSrauts) oi... ave 5 deaids top sone homes eee to base. 
(11) Paleontology of the Section. 
(a) Upper Great Oolite, Groups F to D. 
Most of the limestone-beds in Groups F and D have a very 
coarse oolitic structure, and are crowded with shells largely frag- 
mentary. Polyzoa abound in certain layers, and can be picked 
out in hundreds from the crumbled surfaces. Of most common 
occurrence are slender branching species belonging to the genera 
Heteropora, Ceriopora, and Multiclausa. 
Cidaris-spines are not uncommon, and small gasteropoda, especially 
small specimens of 7-ochus, oceur plentifully. 
