SUPPLEMENT, PLATE XXX. 
PERMIAN. 
Fig. 
1, 2. Chonetes Davidso7ii,^c\\^\\vo\h. 1, 2. Natural size. 1 a, % a. Enlarged. Lower 
Mao;nesian Limestone, Hartley Quarry. Bishopwear- 
mouth, Sunderland. Collection of Mr. James Kirkby. 
(P. 244.) 
3. Streptorhi/ncltus pelargonatus, King. Natural size. Dark compact Limestone, 
Thickley, Durham. A very large specimen. (P. 243.) 
4. Discina Koninchli, Geinitz. Compact Permian Limestone, East Thickley. 
4 c. Shell sculpture magnified. (P. 243.) 
CAHBONIFEROUS. 
5 — 8. Lingula Scotica, Dav. 5. A large specimen obtained by splitting nodule, 
fig. 6. 5 A portion of shell sculpture magnified. 7. 
Another specimen from a split noduJe. 8. Beak enlarged 
to show longitudinal median groove. Ironstone Shales, 
Redesdale, Northumberland. Collection of Mr. R. Howse. 
(P. 265.) 
9. ,, sp.? Vqx\\^^'^ L. squamiformis. Millstone Grit Series, Bishop Thorn- 
ton, Ripley, Yorkshire. (P. 2G7.) 
10. ,, Thomsoni, Dav. Carboniferous Limestone, near Campbeltown, Scot- 
land. Collection of Mr. J. Thomson. (P. 266.) 
11. ,, Credneri, Geinitz. Coal Measures, Durham. (' Carb. Monograph,' 
p. 209.) 
12. 13. Discina nitida, Sow. 12. Natural size. 12 a, b, c. Enlarged, with remains of 
colour marking. From Carboniferous Shale, Boghead 
Quarry, near Hamilton, Scotland. Collection of Mr. 
John Young. 13. Interior of small or attached valve, 
natural size. 13 a. Enlarged, showing muscular impressions 
in a fine state of preservation. From Carboniferous 
Limestone, Arden Quarry near Glasgow. Collection of 
Mr. James Armstrong. (P. 268.) 
14. ,, Craigii, Dav. Carboniferous Limestone, Langside near Beith, Ayr- 
shire. Collection of Mr. R. Craig. (P. 267.) 
15. Athyris pisum, Dav. 15. Natural size. 15 a, 3, c. Enlarged. Carboniferous 
Shale, Brockley, Lesmahagow, Scotland. Collection of Mr. 
J. Thomson. (P. 282.) 
16. Metzia carbonaria, Dav. Carboniferous Limestone Shales, Blackrock Quarry, 
near Bristol. Collection of Mr. Whidborne. (P. 283.) 
17. Terebratula sacculus, Y^^r. hastaia, ^ow. A very large example. Carboniferous 
Limestone, Kildare. Collection of Mr. J. F. Walker. 
(P. 269.) 
18. Pair of spiral coils from the interior of a Spirifer, weathered out and naturally 
detached. From Carboniferous Limestone of Twiston, 
Lancashire. Collection of Mr. John Aitken, of Man- 
chester. (P. 270.) 
