20 MR. R. D. DARBISHIRE ON GREAT-ORME^S-HEAD 



X I J X 1), in one flatter surface of whicli_, in and about a 

 teacup-like depression^ were lo well-marked holes^ of a 

 smaller and more cylindrical form than the last mentioned. 

 Much of the surface of this specimen has weathered away ; 

 but one hole_, |" in diameter, still measures if" in depth^. 

 3 and 4. This Gwydfyd excavation lies at the foot of a 

 vertical cliff, which, however, towards the west runs out into 

 a rugged but still accessible hillside, with numerous exposed 

 ledges of rock in situ. Well-preserved groups of holes of 

 the narrower type occurred at 370 feet and at 435 feet above 

 the sea-level. 



5. After passing over the eminence, and having gained 

 the roadway that leads from the mine-plateau towards the 

 Telegraph-hill, one reaches a mass of limestone rock, 

 the first that breaks the sod on the left of the path as it 

 skirts the northern slope of that hill. In this were to be 

 seen several holes, well formed, and, though exposed, pre- 

 served by their downward opening"^. Height 440-450 feet. 



It is important and instructive, in this rock, to dis- 

 tinguish the genuine P^oZ«5-burrows both from the irre- 

 gular burrows of aerial erosion in the same mass and from 

 the wind- and rain-worn (or perhaps even sea-worn) honey- 

 combing that marks the outcrop a few yards higher up on 

 the path-side, of a mass of superincumbent gritstone. 



The Telegraph-hill consists of this gritstone, and yielded 

 no burrows to my search. 



Walking southward from the Telegraph-hill, one passes 

 first a wide plateau, and then the edges of successive strata 

 cropping out like reefs or low sea-cliffs, the third or fourth 

 of which all but overhangs the isthmus. In the plateau 

 a reef is just traceable through the grass, running south- 

 westerly. 



6. Here occurred, amongst weather-worn beach-pebbles 

 of limestone, a fragment with two holes'^. Height 570 feet. 



On the more exposed reefs from the south the holes 



