248 MR. GARDINER AND PROF, REYNOLDS ON [May 1902, 
D (1). The yellow calcareous flags and slates of Gortnagan Point 
dip near the southern end of the exposure at 70° south 35° east. 
‘Fucoids’ or worm-tracks are very plentiful throughout, and the 
beds have also yielded Rhynchonella Wilsoni, Sow., and Atrypa 
reticularis (Linn.). South of [llaunaportan they are cut off by a 
fault, which runs nearly due east and west. 
D (2). North of the fault the beds, though presenting the same 
lithological characters, are far more fossiliferous, and have yielded :— 
Lindstremia bina, Lonsd. Airypa reticularis (Linn.). 
Favosites. Anodontopsis perovalis, Salt. 
Orthis biloba, Linn. Pleurotomaria Lloydii (Y) Sow. 
O. hybrida, Sow. Pl. sp. 
O. elegantula, Dalm. Murchisonia sp. 
Spirifer crispus, His, Loxonema sinuosum, Sow. 
Sp. elevatus, Dalm. | Horiostoma globosum, Schloth. 
Fthynchonella Wilsoni, Sow. Holopella sp. 
( 
This assemblage of fossils is noticeable for the abundance of 
casteropods, and is suggestive of a Wenlock age for the beds. 
At Coosheg a compact felspathic grit occurs, and below that 
more flags with worm-tracks. Nowhere else in the district are beds 
with Wenlock fossils under- as well as overlain by beds with 
abundant worm-tracks. 
Towards the base the flags become slightly ashy, and in the inlet 
of Coosavaud are faulted against a series of red ashes and sandy 
beds (D 3) which occupy the peninsula of Illaunfraoid. This fault 
is marked by much quartz-veining. 
The bed (D 3), which contains “rhy olitic fragments up to an inch 
in length, is followed by a series of calcareous flags and slates (D 4), 
containing coral-layers composed of Favosites sp. “(). This type of 
rock is characteristic of the Wenlock Beds of the district, and gives 
us good reason to suppose that we are still dealing with strata of 
Wenlock age. These yellow beds extend to the peninsula of 
Foilavaddia, dipping at first 55° south 60° east, but at Foilavaddia 
70° south 25° east (see fig. 16, p. 249). 
They are underlain by ashes of variable character (D 5 & 6) 
dipping at 67° south 35° east, and containing many red and green 
slaty rhyolitic fragments and scoriaceous lapilli. 
D (6) has yielded the following fossils :— 
Favositella sp. Pleurotomaria sp. 
Monticulipora sp. Horiostoma sp. 
Fistulipora sp. Orthoceras sp. 
Pterinea retroflera, Wahl. 
D (7) is a pale, often nodular rhyolite, forming the Point of 
Foilavaddia. Close to the end of the Point it appears to cut 
abruptly across the bed (D 5), but this may be merely due to the ash 
having been deposited on an uneven surface of rhyolite. 
The calcareous tlags and ashy beds (D 8-11), which succeed, did 
not prove fossiliferous. Fort Dunore stands on the calcareous flags 
and slates (D 11). The conglomerate (D 14), which is separated by 
a well-marked fault with crushed material and much quartz-veining 
Phe ete 
