SEA-SCOjRFIOA'S. 31 



scorpions. What curious animals they must have been, using 

 the same limbs for walking, holding their prey, and eating ! 

 Look at the broad plates at the base of the oar -like limbs, or 

 appendages, with their tooth-like edges. These are the plates 

 found by Hugh Miller's quarrymen, and compared by them to 

 the wings of seraphim. You will easily perceive that by a back- 

 ward and forward movement, they would perform the office of 

 teeth and jaws, while the long antennae with their nippers — 

 helped by the other and smaller appendages — held the unfortunate 

 victim in a relentless grasp. And even these smaller limbs, you 

 will see from the figure, had their first joints, near the mouth, 

 provided with toothed edges like a saw. 



With regard to the habits of Sea-scorpions, it would not be 

 altogether safe to conclude that, because in so many ways 

 they resembled king-crabs, they therefore had the same habit 

 of burrowing into the soft muddy or sandy bed of the sea, as 

 some authorities have supposed. Seeing that there is a difference 

 of opinion on this subject, the author consulted Dr. Woodward on 

 the question, and he said he thought it unlikely, seeing that, in 

 some of them, such as the Pterygotus, the eyes are placed on the 

 margin of the head-shield ; for it would hardly care to rub its 

 eyes with sand. Whether it chose at times to bury its long body 

 in the sand by a process of wriggling backwards, as certain 

 modern crustaceans do, we may consider to be an open question. 



If only Sea-scorpions had not unfortunately died out, how 

 interesting it would be to watch them alive, and to see exactly 

 what use they would make of their long bodies, tail-flaps, and 

 tail-spikes ! Were they nocturnal in their habits, wandering 

 about by night, and taking their rest by day ? Such questions, 

 we fear, can never be answered. But their large eyes would have 

 been able to collect a great deal of light when the moon and stars 

 feebly illumined the shallower waters of the seas of Old Red 

 Sandstone times ; and so there is nothing to contradict the idea. 



Now, it is an interesting fact that young crabs, soon after they 



