PLATE ITV. 
DEVONIAN CRUSTACEA. 
Order—MEROSTOMATA. 
Sub- Order-—EuURYPTERIDA. 
Basal joint of a left maxilliped (or ecfoguath) of Pterygotus anglicus, Agassiz, figured 
of the natural size, from the Devonian of Forfarshire. See page 38. 
i, the toothed mandibular border; s, the point of articulation for the proximal end of the 
swimming-foot. (See Plate VIII, fig. 1, 6.) 
‘The original specimen is preserved in the British Museum. 
