﻿PLATE VI. 



Page 



1. Pterichthys testudinarius, Ag. ; dorsal (in part visceral) 



aspect of trunk and tail. — Lower Old Red Sandstone ; 

 Lethen Bar. a.v.l. Anterior ventro-lateral. d. Dor- 

 sal fin. /. Caudal ridge-scales, m.v. Median ventral. 

 p.v.l. Posterior ventro-lateral. [P. 5053.] 217 



2. Pterichthys productus, Ag. ; ventral aspect. — Ibid. e.l. 



Extralateral (operculum). Other letters as above. 



[50111.] 218 



3. Pterichthys oblongus, Ag. ; ventral aspect. — Lower Old 



Eed Sandstone; Gamrie. a.m.d. Anterior median 

 dorsal, x. Caudal fin. Other letters as above. 



[P. 664 a.] 220 



4. Ditto ; ventral aspect. — Lower Old Eed Sandstone ; Lethen 



Bar. a. Anconeal. c. Central. 7. Lateral, m. Mar- 

 ginal, p. Pineal ( ;i os dubium "). p.m. Premedian. 

 t. Terminal. Other letters as above. [50107.] 221 



5. Bothriolepis major (Ag.) ; cranial shield, dorsal aspect. — 



Upper Old Eed Sandstone ; Alves, near Elgin, l.occ. 

 Lateral occipital, m.occ. Median occipital, pt.m. 

 Postmedian. Other letters as above. [38717.] 227 



6. Ditto; imperfect abraded median occipital plate, outer 



aspect. — Upper Old Eed Sandstone; Scat Craig, near 

 Elgin. [35995 a.] 227 



7. 7a, 8, 8a. Ditto : two marginal plates of appendage, the 



first edge-view and in transverse section, the second 

 side-view and in transverse section. — Ibid. 



[35995 c] 227 



9. Bothriolepis hydropJtila (Ag.) ; left ventro-lateral and 

 proximal portion of appendage, ventral aspect. — Upper 

 Old Eed Sandstone ; Dura Den. ar. Articular plate 

 of appendage, r. Inner transverse ridge of anterior 

 ventro-lateral, exposed by removal of substance of this 

 plate, ov. Overlapped inner border of the left ventro- 

 lateral. [26121 a.] 231 



