172 
Bulletin 35 
320 
Antigua the Central Plain intervenes between the two parts, 
while in Guadelupe they are oulj'^ separated bj’ a narrow channel. 
In support of this proposition the physical features of Antigua 
are discussed, and it is shown that the island has not been sub- 
merged since the volcanic period. 
The position and age of the Scotland series of Barbados are 
then discussed, and that series is shown to be Eocene, the lower 
beds being possibly cretaceous and being a remnant of the Atlan- 
tis Continent. 
Page 2S 
The extension, age and position of the Orbitoides bed of 
Trinidad are next dealt with, and some further remarks are add- 
ed on the physical histor\’ of the Caribean Region. 
In 111}’ second “Note on the Manjak Mine’’ I have given a 
brief summary of our knowledge of the origin of asphaltic and 
petroleum deposits. I thought this should have a more extend- 
ed publicity, and accordingly included it in m3’ paper just men- 
tioned. In connection with this I ma}^ notice the recent upheav- 
al of a mudbauk on the South coast of Trinidad. As Dr. Fred- 
holm has given an account in the Mirror newspaper of the causes 
of this phenomenon I will mereh" add that in all essential fea- 
tures it is similar to the mud-lumps of the ^lississippi River. 
These have been full}’ described b}’ L3'ell in the “Principles of 
Geolog}’’’ (tenth edition 1867) Vol. I., p. 447.. His description 
is the best and fullest, but as that of Geikie (Text Book of Geol- 
ogy 1882, p. 386) is the most condensed I quote it : “A singular 
feature of the Mi.ssissippi Bars is the formation upon them of 
mud-lumps. These are masses of clay varying in size from mere 
protuberances, like tree trunks, up to islands several acres in ex- 
tent. They ri.se suddenly and attain heights of three to ten, 
sometimes even eighteen, feet abov’e the sea level. Salt springs 
emitting inflammable gas rise upon them. After the lapse of a 
considerable time the springs cease to emit gas and the lumps are 
worn awa}’ b}’ the currents of the river and the gulf. The origin 
of these excrescences has been attributed to the generation of car- 
buretted hydrogen by the decomposing vegetable matter in the 
