107 
The coulées from the ancient craters appear to have been partly 
under water, as their surface is, in some places, covered with sedi- 
ment and turf; but the lava streams from the modern are bare, rugged, 
and barren, and the craters are surrounded by mounds of loose 
scoriz and ashes. In addition to the comparative view given by 
Mr. Strickland of the phenomena of the Katakekaumene and Central 
France, Mr. Hamilton enters into a more extended investigation of 
points of resemblance, including other portions of Asia Minor. The 
great volcanic groups of Mont Dore, the Cantal, and Mont Mezen, 
Mr, Hamilton conceives are represented by Ak Dagh, Morad Dagh, 
the trachytic hills east of Takmak, Hassan Dagh, and Mount 
Argeus. The modern volcanic period of Central France he com- 
pares with the Katakekaumene, as respects the composition of the 
lavas, their arrangement at different levels, and the cones being 
scattered, not collected in great mountain masses. The Katake- 
kaumene, in Mr. Hamilton’s opinion, exhibits also additional evidence, 
that the disposition of comparatively recent volcanos is coincident 
with the strike of the granitic axis, from the interior of which the 
volcanos have burst forth. The author also alluded to other com- 
parative phenomena noticed in Mr. Strickland’s paper. Lastly, he 
pointed out two distinctions :—in Central France streams of igneous 
products may be traced from the most ancient volcanic masses 
of Mont Dore, but in Asia Minor none have been detected which 
could have flowed from Ak Dagh, or Morad Dagh. In France, 
also, trachytic eruptions occurred during the deposition of the lacus- 
trine limestone; but in the Katakekaumene, they appear to have 
preceded that of the white limestone, or are associated with only its 
lowest beds. 
In conclusion, the paper gives a general summary of the geological 
phenomena of the country south of the Demirji range. 
The relative antiquity of the vast lake or sea in which the strata 
were deposited, cannot be determined, as the micaceous sandstone 
forming the lowest series of beds is apparently destitute of organic 
remains, and Mr. Hamilton, therefore, does not attempt to compare 
that deposit with any European formation. ‘The sandstone, he con- 
ceives, was accumulated upon an irregular surface of schistose 
rocks and crystalline limestone, and before the elevation of the 
Demirji chain. Upon the sandstone were deposited in the north of 
the district the beds of peperite, derived probably from subaqueous 
volcanos; and upon the peperite and the micaceous sandstone, the 
white limestone, which is the highest sedimentary rock. The drain- 
age of the lake, he is of opinion, took place during the earliest 
volcanic eruptions of the Katakekaumene. 
Three well-defined periods of igneous operations may be traced. 
The first is marked by the masses of basalt which cap some of the 
plateaux of white limestone, and were ejected previously to the 
country assuming its present configuration, and to the formation of the 
valleys. Mr. Hamilton considers that the basalt flowed under water, 
and probabty but a short time before the drainage of the lake. 
The second period is characterized by the currents of basalt and 
