PLATE XXYV. 
(The cost of this plate has been defrayed by the Carnegie Trust for the Universities 
Fia. 
of Scotland.) 
Outline sketch of the maxillary bone and mandible of Acrolepis Sedgwicki, Agassiz ; 
from a specimen from the Marl Slate of Midderidge in the Enniskillen Collection, 
British Museum (Natural History), no. P. 8407; natural size. 
Flank-scale of the same species, outer surface, magnified. British Museum (Natural 
History). 
Similar scale, inner surface, magnified. British Museum (Natural History). 
Another detached scale of the same species, outer surface, from the same horizon 
and locality ; magnified. British Museum (Natural History). 
5. Portions of two dorsal fin-rays of Acrolepis Sedgwicki, Agassiz, magnified ; showing 
6. 
Ds 
12. 
Lg; 
the method of transverse jointing, with the exposed sculptured, and the overlapped 
smooth surfaces of the successive joints. From the same horizon and locality as 
the above. British Museum (Natural History). 
Acrolepis Hopkinsi, McCoy. Portions of three bands of flank-scales ; natural size. 
From the Drumgray Coal Shale, Carluke, Lanarkshire. In the Rankine Collection, 
Hunterian Museum, University of Glasgow. 
Acrolepis ortholepis, Traquair; natural size. From the Lower Carboniferous 
(Calciferous Sandstone Series) of Glencartholm, Eskdale, Dumfriesshire. ‘The type 
specimen, in the British Museum (Natural History), no. P. 4081. 
External surfaces, magnified seven diameters, of a group of four flank-scales of the 
same specimen, 
Acrolepis semigranulosus, Vraquair. Outer surface of flank-scale magnified by one 
half. From the type specimen from the Dunnet Shale (Calciferous Sandstone 
Series) of Straiton, Midlothian. In the Royal Scottish Museum, Edinburgh. 
Another scale from the same specimen, similarly magnified, showing the striae 
breaking up into granules on the upper part of the surface. 
Another scale, probably from near the ventral margin, from the same specimen, 
similarly magnified. 
Acrolepis Wilsoni, Vraquair. Scales of type specimen, magnified two and a half 
diameters. From the Yoredale Series at ‘Tarnditch, near Belper, Derbyshire. 
British Museum (Natural History), no. P. 5329. 
Another group of scales of the same specimen, magnified one and a half diameters. 
