BINNIE: MESOZOIC ROCKS OF THE NORTH-EAST COAST OF IRELAND. 57 
The Lias consists of the usual blue clay, stiff shales, and shelly, 
compact, blue or argillaceous limestones. There are also some oolitic 
limestone bands, which occur at "Waterloo, and which were at first 
considered to be representatives of the Oolites, but which Mr, Tate 
has proved to be Lias. 
The Lias is not constant, but is found in various patches along 
the coast. It does not appear to have been much folded before the 
the deposition of the Greensand, as both seem to dip together to the 
same extent. The junction of the Greensand and Lias is rarely or 
never seen, but there must be an unconformity, for there is only the 
lower members of the Jurassic rocks ; and no Oolites, lower Greensand, 
or Gault. 
The shales are indurated at Waterloo, indicating the first stage 
of metamorpliism, they are changed into a so-called Hornblendic 
rock at Portrush, which so resembles the igneous rocks, that for a 
long time it was considered as such, until fossil remains were found 
in it. It was then contested that the igneous rocks were really of 
aqueous origin, since the igneous rocks contained impressions of marine 
organisms. 
The Lias is altered by the heating action due to the basalt, 
and the various dykes which penetrate it. At Portrush the complete 
induration is due to the basalt, which here directly overlies the 
Lias ; this may be taken as representing the ultimate change. 
Mr. Tate has described the occurrence of the following zones in 
the Lias : — 
{a) Ammonites planorbis. 
{h) Ammonites angulatus. 
(c) „ Bucklandi. 
(d) Belemnites acutus (higher than A. Turneri.) 
{e) Middle Lias Marls (Ballintoy.) 
The Lias is underlain by the Avicula contorta shales ; he gives 
the following sections, which serve to indicate their appearance etc. 
at Waterloo. 
{a) Avicula contorta beds are here a mass of indurated grey or brown 
marls ; they form the hill known as Banks Head, where they 
