220 cruise OF THE NEPTUNE 
of Coccosteus sp., holoptychius sp., and modolia angusta. In 
the same strata with these were also seen indeterminable plant- 
fossils. Slightly higher up in the profile, however, in a black 
shale which occurred in two lentiform masses, eighteen inches 
and six feet in thickness, were found numerous plant-fossils.' 
' Professor Nathorst, of Stockholm, who has kindly under- 
taken the examination of these, says that among others are 
archoeopteris fissilis Schmalh. and Arch, archetypus Schmalh., 
both characteristic of Upper Devonian. In examining the 
material collected, Professor Nathorst also found with the plant 
remains some remains of fishes.' 
From the above it will be seen that on the southern side of 
Ellesmere there is a complete succession of strata, bearing fos- 
sils from Middle Silurian age up to the Upper Devonian. These 
strata have an aggregate thickness of 8,000 feet, and form the 
thickest and most carefully measured section of the Silurian 
and Devonian beds of the Arctics. 
On the southern and southwestern parts of North Devon the 
Silurian strata are much thinner than those described by Schei. 
At cuming creek the Archaean gneisses were found overlain 
unconformably by red and purple arenaceous shales and thin 
bedded Sandstones having an aggregate thickness of fifty to one 
hundred feet. These in turn were succeeded by beds of impure 
limestone of light-gray or creamy colour. The beds are usually 
under two feet in thickness, and separated by thinner beds con- 
taining a considerable amount of clay. These light-coloured 
limestones have a thickness of over 1,000 feet in the cliffs on 
both sides of the creek. The sides of the cliffs are covered with 
broken limestone, so that it was impossible to measure a section 
up them, but in two or three places a darker coloured limestone 
conglomerate was found, made up of small pebbles cemented by 
a dark shaly matrix. Fossils are only found in the beds imme- 
diately overlying the dark shales and sandstones of the base. 
