SUPPLEMENT, PLATE XXXVL 
carboniferous. 
Fir. 
1. Prnducfus giganteus, Martin. Hinge-line and well-defined area in the ventral valve. Carbo- 
niferous Limestone Shales, Muirkirk, Ayrshire. Carb. Monograph, p. 141. 
2. „ humerosus, Sow. (cast), and sublcsins, de Kon. (shell). In same specimen, and show- 
ing that both are referable to a single species. Carboniferous Limestone, 
Caldon Low. Collection of Mr. J. Eccles. (P. 306.) " 
3. 4, 5. ,, tessellatus, de Kon. These examples show that same specimen was provided with two 
or more fringes. Carboniferous Limestone, Little Island, Cork, Ireland. 
Collection of Mr. J. Wright. (P. 310.) 
6, 6 a, b. „ Griffithianvs, de Kon. 6. Natural size. 6 a, b. Enlarged. Carboniferous Shales, 
Brockley, Lesmahagow. Collection of Mr. J. Young. (P. 308.) 
7, 7 a, 8. „ carbonnrius, de Kon. 7. Natural size. 7 a.. Portion of shell enlarged. 8. Internal 
cast of dorsal valve, showing muscular and reniform impressions. Carbo- 
niferous Shale, Cutting in Garngad Road, Glasgow. Collection of Mr. J. 
Neilson. ' (P. 309.) 
9. ,, costatus, Sow. Internal cast of ventral valve, on which are seen very numerous, close, 
small, raised tubercles, which are the casts of the perforations that existed on 
inner surface of valve. Carboniferous Limestone, Lanarkshire. Collection 
of Mr. J. Smith. Carb. Monograph, p. 152. 
10. acideatus, M.&rtm. Ventral valve, with perfect spines projecting at right angles to the 
plane of the shell. From rotten Carboniferous Limestone, Cunningham 
Baidland, Dairy, Scotland. Collection of Mr. J. Smith. (P. 311.) 
11. ;, spinulosus, Sow. Ventral valve, with short spines standing erect from surface of the 
shell. Same locality as Fig. iO. (P. 299.) 
12. ,, semireiiculatus, Martin. With edges bent upwards so as to form a band or fringe 
round the shell. Carboniferous Limestone, Little Island, Cork. Collection 
of Mr. J. Wright. (P. 307.) 
13. „ proboscideus, de VerneuiL Carboniferous Limestone, Cruiserath, Drogheda, Ireland. 
Collection of Mr. J. Wright. (P. 31 1.) 
14. ~ ,, longispinus, Sow. With spines almost perfect. From same locality and collection as 
Figs. 10 and II. (P. 298.) 
15,16. „ ,, Sow. 15. Portion of larger valve, greatly magnified, c. External surface, 
showing no evidence of perforations ; s, portion of one of the large hollow 
spines, traversing the thickness of the shell and opening on interior surface 
of the same valve ; B, portions of same valve etched with dilute acid, and 
showing numerous perforations, with substance of shell rising round them ; 
these perforations are displayed chiefly on the raised ribs, the interspaces 
between them being almost smooth. 16. Fragment of interior surface of 
the shell, greatly magnified ; S, opening of large spine on interior surface 
of valve ; B, small perforations, with substance of shell raised round them. 
17. „ semirecticulatus. A portion of inner surface of ventral valve, greatly magnified, s. 
Opening of spine ; b, numerous perforations, with substance of shell raised 
round them. (P. 307.) 
18, 19,20. ., costatus. A portion of larger or ventral valve, much magnified, c, External surface of 
shell, presenting a dense fibrous structure, no perforations existing over its 
surface ; 5, portion of shell slightly etched with dilute acid, showing the 
raised perforations. Previous to being etched the shell, as in c, showed no 
perforations, a, Part of internal cast, the shell being completely removed, 
showing numerous pimple-shaped or conical projections, being casts of the 
perforations scattered over the interior surface of the shell. 19. Fragment 
of the interior surface of dorsal valves magnified, showing the perforations 
scattered over its surface. 20. Diagrammatic view of section of shell to show 
how far the perforations extended, m, Outer imperforated surface of shell ; 
n, interior perforated surface. Carb. Monograph, p. 152. 
21. „ giganteus. Portion of internal cast of dorsal valve, a, Large pimple-shaped, conical 
projections, due, according to Mr. Young, to large perforations ; e, small 
and very numerous projections, due, according to same palaeontologist, to a 
series of smaller perforations that occur amongst the larger perforations all 
over the shell. (P. 296.) 
22. „ scabriculiis. Fragment of internal surface of dorsal valve, greatly magnified. S, Raised 
perforations due to widely-set large perforations ; b, pores due to much more 
numerous and smaller perforations that occur amongst the larger ones all 
over the inner surface of large valve. Carb. IMonograph, p. 169. 
23. ■ strophomena analoga, Phillips. Large valve from Main Limestone of North Hill, 
Campsie, exhibiting numerous vascular impressions that radiate outwards 
from near the beaks to the margin. Collectiorj of Mr. J. Young. (P. 291.) 
