202 RECORD OP SCIENCE FOR 1886. 



iiidiuU'd all or part of the ArcUefin now exposed in New England and 

 soulliward, and not to have extended uny great distance eastward. 



39. Shaler describes the geology of the Cobscook Bay district, near 

 Eastport, Maine, where he finds a series including Devonian, Silurian, 

 and perhaps Archean members, intermingled at various horizons with 

 lava flows, intruded sheets and dikes, and at some points with beds of 

 fragmental volcanic rocks, as ash and breccia. The sedimentary rocks 

 are in greater part fine-grained sandstones and dark-colored shales, with 

 occasional thin beds of limestone. The ash beds are found interbedded 

 with fossiliferous strata at several horizons, and one bed, just below a 

 shale tentatively referred to the Hamilton, is 500 feet in thickness. The 

 volcanic activity appears to have been greatest to the northeastward, as 

 the extravasated matter decreases in amount in the opposite direction. 

 The igneous rocks are in greater part felsites and felsite porphyries, but 

 other varieties are found. The entire stratified series, with a very few 

 exceptions, has an easterly dip of from 20° to G0°, and the beds are 

 much compressed and their fossils contorted. The principal faults 

 range NNE. and SSW., with a subordinate series at right angles, and 

 the dikes generally occur along the fault lines. Provisional names have 

 been applied to the formations, but there is still some doubt about their 

 relation to each other and to other beds along the coast. The basal 

 rocks are crystalline and thought to be Laurentian. Upon them lie 

 what is termed the Campobello group, consisting of about 4,000 feet at 

 least of slaty beds without observed fossils, and probably Cambrian or 

 Siluro-Cambrian in age. They are unconformably overlain by the Cobs- 

 cook group, which also has a thickness of about 4,000 feet. Its upper 

 part yields a Devonian fauna somewhat resembling that of the Hamil- 

 ton, and the Lower Helderberg and other Silurian groups are thought 

 to be recognized farther down ; but the species are mixed and not al- 

 ways determinable. The uppermost group is the Perry series, which 

 constitutes over 2,000 feet of coarse red sandstones, conglomerates, and 

 reddish shales, apparently Upper Devonian or Subcarboniferous.* 



40. At a meeting of the New Brunswick Natural History Society,! 

 Matthew states that on Frye's Island he has recognized the same suc- 

 cession of Silurian strata as is found on the Mascariue shore of Passa- 

 maquoddy Bay, and that the belt of red conglomerate extending from 

 Black's Harbor toward Eastport is Devonian. 



41. In a report of gtudies of parts of northern and western New Bruns- 

 wick, Bailey describes the distribution, stratigraphy, and structure of 

 the several formations and discusses their horizons. The Carboniferous 

 is represented in its upper x>art by gray sandstones, grading downward 

 into bright-red conglomerates and shales of the Lower Carboniferous, 

 which also contains great masses of volcanic material, and in some lo- 

 calities beds of limestone and gypsum. The supposed Devonian is rep- 



* Am. Jour. Sci., Iii, vol. 32, pp. 35-60. 

 t Bulletin No. 5, p. 38. 



