SEA-SCORPIONS 
51 
that they are related to scorpions, and for this reason we call 
them Sea-scorpions. (See Plate II.) 
The Crustacea are a very ancient race, as well as a flourishing 
one; some very old rocks containing undoubted fossils — namely, 
certain slates found in Wales and the Lake District — tell us of a 
1 2 
Fig. 6. — Pterygotus anglicus, six feet long. 
1. Upper side. 2. Under side. (After H. Woodward.) 
time when shallow seas swarmed with little articulate animals 
known as trilohites. 
The best-known and largest of the Sea-scorpions is represented 
in Fig. 6. It has received the name Pterygotus (or wing-eared), 
from certain fanciful resemblances pointed out by the quarry men. 
It was first discovered, along with others of its kind, by Hugh 
Miller, at Carmylie in Forfarshire, in a certain part of the Old 
Eed Sandstone (see Table of Strata, Appendix I.) known as the 
