84 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 
~ would carry it over much of the Cobequids just tangent to the surface 
and tnto the rest of the massif, nowhere cutting it more than four hun- 
dred feet below its highest point. This close correspondence between 
the two plateau surfaces is explained by the assumption of one continu- 
ous peneplain as once having covered both plateaus and the intervening 
space. At the same time, it is possible that long low residuals of the 
“ Unaka” type? overlooked the peneplain in the region of what is now 
the Cobequid belt. 
Tue New Brunswick HicHtanps. — The lack of good topographic 
maps and of numerous accurately determined elevations is especially 
felt when the attempt is made to carry the peneplain facet into New 
Brunswick. Yet the grouping of facts summarized in the one-quarter 
inch map of the Dominion Survey with those derived from written 
reports seems to show that the facet is represented over considerable 
areas of the upland. The strongly folded Cambrian, Silurian, Devonian, 
and Lower Carboniferous beds wrap about the pre-Cambrian core which 
runs parallel to Chignecto Channel and the Bay of Fundy shore. From 
the eastern end of the range to a point about thirty miles northeast of 
St. John, all these rocks stop off at a general level of from 1,000 to 
1,200 feet. The surface is gently rolling and very comparable to that 
of the Cobequid plateau. Still farther to the west it sinks to 
the 600-foot contour, where it crosses the St. John River, only to 
rise again to 1,200 feet and more on the northern arm of the massive 
angle of the New Brunswick ancient crystallines running to Chaleur 
Bay. Monadnocks like Bald Mt. dominate the peneplain. Below it 
lie entrenched longitudinal valleys presumably of subsequent origin 
(Bailey and Matthews, ’72, p. 15). 
NortH Mountain, Diasy Neck, anp Lone Isuanp. — Lastly, the 
upland surface of the great lava ridge that stretches with interruptions 
from Cape Blomidon to Briar Island, a hundred and twenty miles away, 
admirably represents the peneplain facet (Plates 4 and 5). Extending 
the latter in imagination from the Southern Plateau to the New 
Brunswick highland, the nearly plane surface thus produced is found to 
be tangent to the summit of the intervening “mountain.” From 
Blomidon to Digby Gut, the average elevation of the flat-topped and 
truncated ridge is about 550 feet, matching well with the 500-foot 
sky-line of South Mountain. Southwest of the Gut, the ridge-plateau 
breaks up into two subordinate ridges separated by a long valley. 
Their crest-lines accord in elevation as they sink to 120 feet on Briar 
1 Hayes, 19th Ann. Rept. U. S. Geol. Surv., 1899, Pt. II. p. 22. 
