PLATE II. 
DEVONIAN CRUSTACKA. 
Order—MEROSTOMATA. 
Sub- Order-—EuRYPTERIDA. 
Vic. 
1. Pterygotus anglicus, Ag. (natural size), from the indurated shale overlying the 
“ Arbroath Paving-stone,” Turin Hill range, near Forfar. One of the most entire 
specimens obtained. See page 34. 
The dorsal surface is exposed to view; but the organs of the mouth, &c., are 
seen impressed through the integument of the head-shield. 
From the Museum of James Powrie, Esq., ?.G.S., Reswallie, Forfar. 
2. Pterygotus anglicus, Agassiz. Probably about the third, or fourth body-segment of a 
very large individual, the original measuring 18 inches in breadth and 44 in 
depth. From the Devonian of Forfarshire. See page 41. 
The original specimen is preserved in the British Museum. 
