TRANSACTIONS OF THE SECTIONS. 93 
parencies. in the microscope, were singularly instructive and beautiful. They were 
formed of true bone, and thickly speckled over towards their bases with the charac- 
teristic life points, whereas towards the apex they abounded in anastomosing canals, 
which, throwing out to the sides and point of each tooth numerous minute parallel 
branches, gave to the bone in these parts a structure very much approximating to 
that of ivory. It would seem as if in these ancient teeth we had caught bone passing 
into that finer substance of which the teeth of all the higher vertebrata are composed. 
From the character of the surface of the jaw of Coccesteus on both sides, it seems to 
have been covered, said Mr. Miller, like jaws of the more modern type, by integu- 
ments. 1t was altogether an internal, not a dermal bone, and was probably the oldest 
internal bone that had as yet presented its structure to the microscope. And itis surely 
᾿ Not uninteresting to see the osseous substance,—destined to perform so important a 
part in the animal ceconomy,—presenting in this early age its distinguishing charac- 
teristics, especially those numerous life-points from which its organization begins, 
and which still remain opén as the sheltering cells in which vitality should reside. 
Was it impossible, in tbe nature of things, that life should be equally diffused over 
hard and rigid earth, built up into this new animal substance, bone ὃ and was it there- 
fore merely thickly sown over it in hollow microscopic points ? Is bone rather strongly 
Sarrisoned by vitality than itself vital ? 
Mr. Miller then went on to exhibit several specimens of a well-marked though doubt- 
fully interpreted bone, which, in all the ordinary fishes, and in almost all the Ganoids, 
forms the largest and most important part of the scapular belt or ring, and which 
appears first in the lower old red sandstone. The gill-cover also appears in the 
same deposits for the first time; and Mr. Miller went on to show how they are ne- 
cessarily connected in the scheme of creation, and that the one of necessity accom- 
panies the other. At the close of his paper, Mr. Miller exhibited a set of the remains 
of Asterolepis, and made large acknowledgments to Mr. Robert Dick of Thurso, to 
whom he cowed all the finer specimens, and whose labours had done more to introduce 
this fish to the palzontologist than those of any other man, whetherin Russia or our 
own country. 
On peculiar scratched Pebbles and Fossil Specimens from the Boulder 
Clay, and on Chalk Flints and Oolitic Fossils from the Boulder Clay in 
Caithness. By Hucu Mityer, Edinburgh. 
Mr. Miller began by stating that, when examining, a good many years ago, the boulder 
clay of Ross and Cromarty, in the vain hope, as it proved, of finding in it organic remains 
belonging to itself, he was struck by a peculiarity in the dressing of the smaller 
pebbles which he had not seen described or adverted to by any writer on the subject. 
He was aware that many of the larger boulders which it contains are scratched and 
polished like the rocks on which it rests, but he was not prepared to find the smaller 
pebbles scratched scarce less characteristically than the larger ones in every case in 
which they were not of too coarse a grain to retain the markings, or of too hard a 
quality to receive them originally. If of limestone, or of a coherent shale, or of a 
close, finely-grained sandstone, or of a yielding trap, they are scratched and polished 
invariably on one, most commonly on both their sides; and it is a noticeable circum- 
stance, that the lines of the scratchings occur, in at least four cases out of every five, 
in the lines of their longer axes. When decidedly oblong or spindle-shaped the 
scratchings run lengthwise, preserving in most cases on the under and upper sides a 
parallelism singularly exact ; whereas when of a broader form, so that the length and 
breadth nearly approximate, though the lines generally find out the longer axes and 
run in that direction,—they are less exact in their parallelism, and are occasionally 
traversed by cross furrows. Of such general occurrence is this longitudinal lining on 
the softer and finer-grained pebbles of the boulder clay, that it forms the special cha- 
racteristic of the deposit on which the geologist can with the greatest certainty rely 
for purposes of identification. 
Though in many cases, as on the western coasts of the mainland of Scotland, in 
the islands of Skye and Rum, with several of the other Hebrides, in Sutherland- 
shire, and in various localities in the neighbourhood of Edinburgh, Mr. M. had 
found the scratched and polished surfaces. dissociated from the boulder clay, in no 
