ON A TRIASSIC OUTLIER IN THE ENGLISH CHANNEL. 313 



25. On the Existence of a Submarine Triassic Outlier in the 

 English Channel, off the Lizard. By E. N. Worth, Esq., 

 F.G.S. (Read May 12, 1886.) 



It is with great pleasure that I am able to report to the Geological 

 Society the existence of a submarine Triassic outlier in the English 

 Channel, off the Lizard. The possibility of the presence of Triassic 

 rocks in the Channel-area has been more than once suggested, and 

 the occasional dredging of a fragment of sandstone has strengthened 

 the hypothesis ; no distinct evidence has, however, until now been 

 procured. 



A short time since Mr. Matthias Dunn, of Mevagissey, who is 

 intimately acquainted with all the conditions of the Channel fishery, 

 called my attention to the fact of the frequent occurrence of sand- 

 stone fragments in the bed of the Channel in a certain direction, 

 and at my desire promised to supply me with a series of specimens. 

 This he has now done, and the facts thus revealed are of a very 

 remarkable character. All the examples were brought up entangled 

 in the hooks of the fishermen's " long lines," which are laid along 

 the sea-bottom for distances ranging even up to six miles. The 

 positions from which the rocks come can therefore be ascertained 

 with considerable precision ; and each specimen or group of 

 specimens was accompanied by its compass-bearing on some well- 

 known point of the land, and the distance thence in miles. The 

 bearings are magnetic and strictly correct; the distances are 

 estimated, and therefore liable to a certain amount of error ; though 

 from constant practice and their knowledge of the peculiarities of 

 the sea-bottom the fishermen are singularly accurate in these 

 estimates. 



The evidence that the rocks were in situ when entangled (partly 

 by the marine growths upon them, and partly by their irregularities 

 and the holes bored by Pholades) is clear. With two exceptions 

 only, to be referred to hereafter, the specimens retained the charac- 

 ters of the original bedding. The upper surfaces of the fragments 

 are, as a rule, bored ; the lower are either free from marine organisms, 

 or show only such minute ones as would grow on the under surface 

 of a slab of rocl^ that was gradually working loose from its parent 

 reef. In all probability most of my specimens were detached from 

 their places by the hooks that brought them to the surface. 



The list of these rock specimens is as follows : — 



1. Lizard, 10 miles N.W. — Eine-grained, soft, red Triassic sand- 

 stone, in layers 1| to 2 inches thick. 



2. Lizard, 15 miles ^N^.W. — Triassic sandstone of coarser grain, 

 mottled red and grey. 



3. Manacles Hocks, 16 miles N.W. — Fine-grained soft sandstone, 

 grey, with a passing red tinge in places, in parts highly micaceous, 



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