Smvth — The Carboniferous Coast-Section at Malahide. 11 



and it is taken to have the doivn-throvj to the N. To quote the memoir 

 referring to the beds S. of this fault : — 



"These are precisely similar in lithological character to beds which are 

 frequently found at the base of the limestone in the S. of Ireland (and also 

 in S. Wales), and are called therefore the Lower Limestone Shales. . . . 

 Just on the S. side of the niartello tower here there is a sudden twist in 

 the beds, beyond which there is an equally sudden change in their litho- 

 logical character. It is supposed, therefore, that a fault traverses the 

 limestone here, having probably a down-throw to the N., and being perhaps 

 connected in sovie %vay with the one just described as to be observed in the 

 railway, where, however, the throw is in the opposite direction."'^ (The italics are 

 mine.) 



The amount of down-throw^ to the south of this railway fault is estimated 

 on p. 56 of the memoir as greater than 750 feet — a figure curiously close to 

 my estimate for the Carrickhill fault (see below, p. 17.). 



"With regard to the other two faults, the C.G. fault can, as before 

 mentioned, be seen in the cliff. It was, however, impossible to tell whether 

 it was a dislocation of any importance, until the corresponding fossiliferous 

 bands were discovered on either side. But it is curious that this fault is net 

 even mentioned in the memoir.' 



I did not myself recognize the northern fault as such during my first 

 visit. It seemed to be simply an anticline somewhat " stretched " at the 

 crest. Only by noting down in detail the beds and their fossil contents in 

 either limb of this "anticline" did it become clear that correlation was 

 impossible. 



II. — Fauna* and Coekelation. 

 Block E, upper part (M 1, 2, 3, 4«, b, c).' 290 feet = C^. 



Abundant — 



Zccphrentis densa, Carruthers. 



Syringopora 9, Vau. 

 Athyris cf. glabristria, Phill. 

 Syringothyris laviinosa, McCoy. 

 Conocardium fusiforme, McCoy. 



1 p. 56. 2 The context showrs that this is " stratigraphical " throw. 



2 By the courtesy of the officers of the Geological Survey of Ireland, I was able to 

 consult the MS. 6-inch map, from which the 1-inch was reduced. I there find three 

 parallel lines drawn E. and W., one at this fault, the other two close to it to the S. 



* Only corals and brachiopods are recorded, except in rhe case of a few molluscs 

 which happen to he abundant. 



5 These symbols refer to groups of beds as indicated on the map. 



c2 



