ROBERTS — DISTRIBUTION OF CEPHALASPIS AND PTERASPIS. 107 



stone interstratified, which must not be confounded with the true 

 Old Red comstone which is quarried and tunnelled into beyond this 

 quarry — and I have lately met with some bits of fish-armour, with 

 cunningly convoluted stria?, fragments of a related though, as yet, 

 undescribed genus. These also occur in a brown-red coarse grit, at the 

 Wall Hills, near Ledbury, though higher in stratigraphical position. 



I have said that through the Whitbatch portal we enter a very 

 fine field of research, but our route must be advisedly taken ; and I do 

 not recommend another halt in our march until we have left Down- 

 ton Hall and its woods behind us, and are looking down from the high 

 grounds of Hayton, upon the beautiful dale of the Corve. If we 

 trace northward from Upper Hayton the lines of cornstone in out- 

 crop parallel to the course of the Dale, we shall come to some notable 

 exposures. 



At some points, Hayton's Bent, for example, they are cupriferous, 

 though the poorness of the ore obtained, (a carbonate), has yielded 

 but little copper, and failure has attended the works. And at another 

 spot, near the farm-buildings of Downton Hall, they have yielded an 

 ore of lead, in the well-known form of cubic galena. 



But it is for fishes we are searching, not metals. There is a small 

 quarry in a field at the top of Hayton, which one would think a 

 terrible place from its being called the " Devil's mouth," but there 

 is nothing alarming about its appearance, nor has it any strange 

 connections that I could see, save its treasures of Cephalaspid fish. 

 I think I never saw Pteraspis Lloydii of equal size to those I have 

 taken in this quarry, though I could meet with no other species. 

 The stone is here a fine-grained light-coloured sand-rock, inter- 

 stratified with true cornstone. Two miles east of this place, in the 

 Upper Cornstones of Hopton Cangeford, the monarch of the Cepha- 

 laspides in point of size, the great C. asterolepis, was found by Dr. 

 Harley. More of this noble fellow when we mount up to him in 

 time, and ascending order of beds. 



On the same horizon, and yielding more or less evidence of their 

 former life are the cornstones of Hall's Barn, near Kidderminster, 

 and of Cradley, near Malvern. In both places I have found frag- 

 ments of Cephalaspis and Pteraspis in abundance ; but I need hardly 

 remind the collecting geologist that good scutes are of very unfrequent 

 occurrence ; the majority of specimens having been laid with the breccia- 

 like gravel, whose weight and unequal pressure were enough, even if 

 motionless and undisturbed by currents, to have broken up the shell- 

 like plates. And in fact such an amount of grinding did actually 

 take place among the shallows and pebble-reaches of the Old Red 

 lagoons, that more than one layer of coarse grit lying above the 

 lower cornstone is seen by a lens to be crowded with blue and purple 

 atoms of fish-shell, the triturated remains of many a good Pteraspis. 



Steering north, with a slight easterly inclination, from the Hayton 

 quarry, we shall find several breakages into the lower cornstones, 

 near the apex of the ridge, at Sutton and Bouldon and Tugford. 

 Pteraspidean plates are to be found at each of these places, and a halt 



