118 REPORTS ON THE STATE OP SCIENCE. 



boundaries, and contain cores of coarse gritty material, which come out 

 cleanly, and in substance match 'with the matrix of the overlying con- 

 glomeratic grit. The actual terminations of the cavities were not found. 

 The appearances lead to the conclusion that the sandstone had been 

 bored after the consolidation of the Lower Comley sandstone by some- 

 organism capable of removing the cementing material by solution, and 

 of expelling the quartz and other grains thus loosened. Except in the 

 matter of length and shape, the cavities present some analogy to the 

 modern Pholas borings in the consolidated Triassic sandstones of the 

 south Devonshire coast. That they were formed after consolidation is 

 rendered the more probable from the fact that the overlying conglome- 

 rate, both here and at the Comley Quarry, contains subangular and 

 angular fragments of similar compact greenish sandstone. 



No. 29b. — In order to confirm the evidence of unconformity ex- 

 hibited in the last-mentioned excavation, a hole was made on the 

 opposite or south-east side of the summit, where clearly bedded coarse 

 grit of normal Quarry Eidge grit type, with the same dip of 45° to a little 

 south of east, was disclosed. 



No. 29c. — As No. 29b did not show the underlying rock, another 

 excavation was made a few yards away. Tn this similar grit having the 

 same dip was exposed, but more incoherent and of an ochreous colour, 

 and, underlying it, a breccia of angular fragments of greenish sandstone, 

 separated more or less from one another by coarse, gritty material. 

 Underneath this, again, and partly protruding into it from below, was 

 a rib of solid green sandstone containing a calcareous band, the dip of 

 which was clearly north of east and at a higher angle than that of the 

 grit above it. The divergence between the strikes of the two kinds of 

 rock, both here and in excavation No. 29a, is about 30°. The calcareous 

 band contained several specimens of minute Ostracoda with a thin 

 chitinous shell and a shagreened surface. 



No. 29J. — On the north-western side of the summit, and about 

 25 yards to the south-west of No. 29a, some large blocks of rock pro- 

 truded from the surface, which I refer to the conglomeratic grit, but 

 they are not truly in situ. On removing two of these, green sandstone, 

 containing a dark, calcareous band, was found, and some pinkish lime- 

 stone nodules close to it yielded a profuse number of fossil fragments. 

 Among these there are Olenellus, sp., apparently identical with 0. Cal- 

 lavei Lapw., Ptychoparia ? unnio Cob}x>ld, , Ptychoparia ? attleborensis 

 S. & F., Microdiscus helena Wale. '?., Micinacca ? possibly M. ? ellipso- 

 cephaloides Cobbold, a fragment of a rather large trilobite not referable 

 to Olenellus Callavei, but possibly belonging to the same genus, Kutorgina 

 cingulata Bill., Linnarssonia, sp. (the same species that is so abundant 

 in the Comley Quarry), Acrolhele?, and some small Ostracoda. 



This fauna, so far as the very fragmentary material has been worked 

 out, is almost exactly the same as that of the Olenellus horizon of the 

 Quarry Eidge, but it does not necessarily follow that it is the same band, 

 and it is not certain whether the nodules are in situ, or whether they are 

 pebbles collected in a hollow behind the dark calcareous band. The 

 evidence .points to the conclusion that the greenish micaceous sandstone 

 of Eobin's Tump belongs to the Lower Comley sandstone as previously 



