LOWER MAGNESIAN LIMESTONE OF SUNDERLAND. OTS 
( 7 Brown and yellowish, cellular, unstratified, tufa- 
like limestone ... se 25 
(An irregular line of ‘division. ) 
8 Grey Gmottled), hard, subcrystalline, thick- bedded 
limestone 18 0 
(A weil marked irregular ‘line of divi ision. ) 
9 Dark brown, pseudo-concretionary, rudely bedded 
limestone; thinning out to west ... fhe 
Lower 10 Chocolate- hued, or chocolate mottled with brown 
Limestone. and yellow, hard, very close-grained, ribboned 
limestone; very hard and crystalline at top 5 0 
11 Chocolate and brown mottled limestone of irre- 
gular structure ... 2 
12 Yellow, hard, close- -grained, massive, ‘occasionally 
dendritic limestone; bright chrome hued in places, 
and with partings of brown clay ... 9 
13 Yellow, very compact, flaggy and slaty limestone 1 
(14 Yellow or brownish, earthy, laminated lime- 
stone or marlslate : ee 
15 Yellow, soft marl 
16 Brown ‘clay, fine and unctuous 
17 Dark grey or black shale ... 
18 Grey, hard ee graduating into greenish 
erey below «a 
19 Marlslate: dark erey and “soft at top; brownish 
black, tough and clayey at bottom 
20 Brown clay, fine and unctuous 
Lower Red 21 Yellow sand or sandstone, with a thin, white coat- 
Sandstone. ing on top, and very incoherent... wan 
o 
Marlslate. 
oo ee CCoO- 
= o> oO bt ped bet CD oo 
This is one of the most interesting sections of the lower por- 
tion of the Permian series that occurs near Sunderland; and 
besides serving to illustrate the present paper, it is well worth 
publication on its own merits, more especially as the quarry in 
which it is exposed is now being filled up with rubbish. 
The yellow incoherent sandstone (21), at the base of the 
section, is the top of the lowest Permian sub-division=the 
Lower Red Sandstone. It has only been exposed once at the 
bottom of the quarry. 
The overlying~ calcareous slates (14-20) represent another 
member=the Marl Slate. It attains a thickness of three feet. 
The lower portion is dark grey, argillaceous, and tough; the 
middle portion is a lighter and greenish grey, hard, and more 
calcareous; the higher portion is yellow, moderately hard, and 
but slightly argillaceous. A band of unctuous clay runs through 
the centre of this marl slate, and another separates it from the 
underlying sandstone. From the lowest portion (the darker 
lamin), I have obtained poor specimens or fragments of Palao- 
