a Rg AC Ly 
. 2, Pterygo-quadrate apparatus of the same species, showing three constituent elements ; 
6 “J Sa Ot 
STRUCTURE AND AFFINITIES OF THE PLATYSOMID 4. 391 
PLATE V. 
Fig. 1. Restored figure of Cheirodus granulosus, Young sp. From a suite of specimens from 
North Staffordshire, in the collection of J. Ward, Esq., F.G.S. 
b] 
natural size. North Staffordshire. 
. 3, Pterygoid bone, separate, seen from the oral aspect. North Staffordshire. 
. 4, Maxilla, seen from the internal aspect, showing the supermarginal band of tooth-like 
tubercles. North Staffordshire. 
. Maxilla, seen from the external aspect. 
. Splenial element of mandible, inner or oral aspect. North Staffordshire, 
. The same bone from the outer aspect. 
. The same bone, seen from above. 
. Dentary element of the mandible of a smaller specimen, seen from the outer aspect ; the 
external layer of the bone injured in the middle. Manchester Coal Field. 
. 10. Diagrammatic restoration of the palato-quadrate, mandibular, and opercular arrange- 
ments in Cheirodus, as seen from the inner aspect. 
. 11.- Interoperculum, seen from the inner aspect. Manchester Coal Field. 
. 12. Clavicle, seen from the inner aspect. Manchester Coal Field. 
. 13. External aspect of a flank scale belonging to a very large disjointed specimen; natural 
size. Manchester Coal Field. 
. 14, Inner aspect of a similar scale. 
PrATE: Vial. 
. 1. Restored outline of Platysomus striatus, Ag. 
. 2. Scale from the flank of Platysomus striatus; magnified two diameters. 
. 3. Scale from the flank of Platysomus parvulus, Ag.; magnified two and a-half diameters. 
Fig. 4. Internal surface of a similar scale. 
Fig. 5. Restored outline of Platysomus parvulus, Ag.; the scales of the body omitted. From a 
suite of specimens in the collection of J. Ward, Esq., F.G.S. 
6. Roof bones of the posterior part of the top of the head of Platysomus parvulus, as shown 
in an ironstone cast of their inner surfaces. Fenton, Staffordshire. 
7. Median superethmoidal and anterior frontal bones of the same species; magnified two 
diameters. 
. 8. Preoperculum of Pl. parvulus, internal aspect ; magnified two diameters. 
9, Maxilla of Pl. parvulus ; magnified two diameters. 
10. Branchiostegal ray, detached, of Pl. Forsteri, Hancock and Atthey. 
11. Maxillary teeth of Pl. parvulus ; magnified fifteen diameters. 
12. Restored outline of the bones of the outside of the head and shoulder girdle of 
Paleoniscus Freieslebeni, Ag. 
. 13. Restored outline of the bones of the outside of the head of Dapedius. 
. 14, Scales from the flank of Gyrodus frontatus, Ag.; seen from the inner surface, and 
magnified two diameters. 
. 15, Scales from the caudal region of the same species, also seen from the inner aspect. 
. 16. Scales of Palconiscus Freieslebeni; seen from the inner aspect, and magnified six 
diameters. 
VOL. XXIX. PART I. oH 
