﻿Prof. Milne and, Alex. Murray — RocJcs of Newfoundland. 255 



Ij'ing as they do at the very base of the Sihirian. My last oppor- 

 tunity of seeing these rocks was whilst coasting along the shores of 

 Bonavista Bay, especially in the neighbourhood of Cutler's Head, 

 where they are exposed in cliffs several hundreds of feet in height. 

 The rocks are fine-grained, chloritic, and argillaceous. In many 

 places they are coloured with red oxide of iron. Some of the rocks 

 of this neighbourhood of an amygdaloidal character appeared to be 

 altered diorite. 



On the western side of this headland there is a deserted monument 

 of folly in the form of a small quarry, which was vigorously worked 

 upon under the impression that the compact argillaceous-like rock 

 of the cliff was a mass of tin-stone. 



Further up the bay conglomerate and more igneous rocks of a 

 chloritic character and rich in kaolinized felspar were observed. 



Potsdam and Calciferous.^ — Still ascending in the series, the next 

 members are those of the Potsdam and Calciferous groups. These 

 are to be seen in the northern and western parts of tlie island. 



The former of these groups consists of dark-coloured slates and 

 conglomerates, containing recognized Potsdam fossils. The series 

 amounts to upwards of 5400 feet in thickness. Penetrating these 

 rocks I found dykes very similar to those I observed before, such as 

 felsites and highly chloritic melaphyres containing quartz. 



The Calciferous series, which overlies the Potsdam, is one which 

 presents very different characters to any of the preceding. It is 

 well exposed in the western parts of the island upon the northern 

 side of the Port au Port Peninsula, where it consists of definitely 

 stratified grey limestones rich in fossils, — large Ortliosceri, Corals 

 and Maclurea being very noticeable. These limestones weather into 

 thick columnar forms, divided horizontally by joints, just as if so 

 many huge discs with rounded edges had been piled one above the 

 other. 



By the action of the sea and other causes, several caverns have 

 been excavated. Two of these I explored. One was wide and open, 

 and about 70 feet in length; the second, which was narrow and low, 

 was about 130 feet in length. Some of these, on future exploration, 

 may yield remains, beneath the bed of clay with which their floor 

 is covered, which may be of interest in connexion with the study 

 of the modern fauna of the island. 



Quebec Group. — At the base of this group we get a vast series of 

 graptolitic shales, amounting to about 4000 feet in thickness. 

 Above these shales we have a large display of serpentines and 



1 The passage upwards from the Paradoxides slates is very well displayed in Con- 

 ception Bay, where there is no evidence of any want of stratigraphical conformity ; 

 but it is difficult to tell in what part of the section the Primordial ceases, and the 

 Potsdam pi-oper begins ; a great mass of sandstone occurs at Kelly's Island, and 

 there are alternating sandstones and black shales or slates, which form the largest 

 island in the bay — -Bell Island. The whole of these strata hold in greater or less 

 abundance Cruziana similis, Billings, Eophyton Linnceanum, Torrell, several 

 species of Livgula, and other forms Avhich Mr. Billings was disposed to think were 

 of Upper Potsdam type. These strata differ considerably from the beds Mr. Milne 

 quotes, on the north and west sides of the island, which are probably higher 

 measures. — A.M. 



