EiD'ijpterid Remains in Carhoniferoics Shales of Scotland. 507 



of sand and mud, the pauses in the deposition being just 

 sufficient to allow each film of sand or mud to harden ere 

 the next was laid down upon it. 



The position of this plant-bed has been definitely fixed by 

 Mr Kirkby having identified a limestone which lies a few 

 feet below it as the equivalent of one which occurs at Bellow 

 Ness, west of Anstruther, the position of which Mr Kirkby 

 has found by actual measurement to be 3135 feet below the 

 St Monans Limestone — the Fife equivalent of the Hurlet 

 Limestone. It is thus certain that the Eurypterids, at a very 

 early period, were abroad in the east of Fife in considerable 

 numbers. 



From the foregoing facts the following conclusions may be 

 safely inferred : — 



1st, That there cannot be any reasonable doubt that indi- 

 viduals of the family of Eurypterids were extremely abundant 

 during the Carboniferous period in the places and positions 

 detailed. 



2d, That as all the pieces of Eurypterid skin are profusely 

 sculptured or, more correctly, embossed with various patterns 

 representing lozenges, crescents, round dots, crimpings of 

 the skin, or projections of it into hair-like bristles, the idea 

 of a variety of species is suggested, and would be entertained 

 were we sure that a change of style of ornament was not 

 merely indicative of different parts of the body of the same 

 individual. It is, therefore, much to be desired that a whole 

 Eurypterid might be captured anywhere, and the ornament 

 of the head, the body, the limbs, or the tail figured and 

 described, so that we might know whether a difference of 

 pattern was individual or specific. Till that is done we 

 must content ourselves with the conjecture that variety of 

 design may mark distinctions of species. 



3cZ, From the almost invariable occurrence of Eurypterid 

 with scorpion remains, showing that they were companions 

 in life as they are now neighbours in death, we may infer 

 there was not in Carboniferous times any great essential 

 difference in their economy or habits, seeing there was none 

 in their habitats. In some localities, such as Hailes and 

 Kingscavil, the conditions indicate burial in sediment, but 



