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Proceedings of the Royal Irish Academy, 
a turbinoid coral, nearly an inch and a quarter in diameter. The plates 
were numerous, but they were only seen to pass from the rim to about 
half way to the centre of the calice, possibly owing to its being deeply 
concave. Unfortunately, in trying to detach the specimen, which 
was slightly in relief, it broke into fragments. To all appearances it 
belonged to a large species of Montlivaltia : the circularity and large 
size of the calice are against its being an isolated corallite of Isastrma 
MurcMsoni ; a species forming a reef in the Lias at Lussay, on the 
opposite coast of the island. 
The succeeding rocks, limestones of a dark colour, and of a less 
crystalline character than those last described, are highly fossiliferous ; 
some being formed entirely of fragments of shells, amongst which were 
found portions of a small ammonite, and detached valves of a shell 
resembling Avicida decussata. 
Shales and other limestones follow ; and these are distinguished by 
an immense number of GrypTicda obliquata, and other Liassic fossils. 
All the foregoing stratified rocks gradually fall from a nearly 
vertical position, which obtains at the junction of the marble with the 
syenite at Camus Smalaig, to about 20 degrees — apparently the angle 
of the highest gryphaea beds near Suishnish Grlen. In no part of the 
section, which does not exceed a mile in extent, was any certain case 
of stratial disruption or unconformability observed. 
Reverting to the marble, both MaccuUoch and Geikie express 
themselves in favor of its being a metamorphic rock of Liassic age, the 
contiguous syenite having been the metamorphosing agent. Some, 
it would seeni, are indisposed to accept this conclusion. With all 
due deference to the authority of that eminent geologist, Mr. Geikie," 
Dr. Hunt avers he ^'cannot help suggesting that a re-examination of the 
district of Strath would show that the highly metamorphosed crystalline 
limestones, holding serpentine, and associated with syenitic rocks, 
belong to an older system (probably Laurentian), and are thus 
distinct from the nearly horizontal fossiliferous limestones near by, 
which are locally altered by intrusive rocks. Unfortunately for this 
suggestion, all the evidences are against it. And it so happens that 
the fossiliferous limestones referred to, which have an inclination of 
about 20 degrees, regularly graduate in angle, and to some extent in 
structure, into the '^highly inclined metamorphosed crystalline lime- 
stones while the short space between the marble, and the beds nearest 
to it yielding the fragments of ammonite, (fee, shows no want of con- 
formability. And what is further confirmatory of the conclusion, ob- 
jected to by Br. Hunt, is the repetition of a similar stratigraphy on 
the other or Torrin side of the syenite. The difference between the 
angle of the crystalline marble and that of the highest of the fossilife- 
rous limestones, has evidently been caused by the latter being at the 
gTeatest distance from the syenite : the limestone would not, as a 
consequence, be so much tilted as the marble. 
* " Silliman's American Journal," March, 1870, p. 186. 
