EXPLANATION OF PLATE 1. 
6 
A. 10. represents a dyke and protruded mass of Granite, 
intersecting and overlying stratified rocks of the Primary 
and Transition series. A. 11. represents the rare case of 
Granite intersecting Red Sandstone, Oolite, and Chalk.* 
Sienite, Porphyry, Serpentine, Greenstone. 
Closely allied to Granitic Veins, is a second series of 
irregularly injected rocks, composed of Sienite, Porphyry, 
Serpentine, and Green Stone (b. c. d. e.) which traverse the 
Primary and Transition formations, and the lower regions 
of the Secondary strata ; not only intersecting them in va- 
rious directions, but often forming also overlying masses, 
m places where these veins have terminated by overflow- 
ing at the surface, (b'. c'. d'. e'.) The crystalline rocks of 
this series, present so many modifications of their ingre- 
dients, that numerous varieties of Sienite, Porphyry, and 
Greenstone occur frequently in the products of Eruptions 
from a single vent. 
The scale of our Section admits not of an accurate repre- 
sentation of the relations between many of these intruded 
rocks, and the strata they intersect j they are all placed, as 
t le injections of Basaltic and Volcanic matter 
w uch that portion of the section is intended to illustrate, 
the Phenomenon of Granite intruded into 
in th ^°*'™ntion, in the hill of St. Martin, near Pont de la Fou 
described by M. Dufrenoy in the Bulletin de la 
At^W *'rance, Tom. 2. page 73. 
ta- a n Meissen in Saxony, Prof. Weiss has ascer- 
^ c t e presence of Sienite above strata of Chalk ; and Prof, 
^auman states, that, near Oberau, Cretaceous rocks are covered by 
roc^***' ^®t^heila and Neiderfehre, the Cretaceous 
stone '‘ftizontally on Granite ; at both these places the Lime- 
tions ®/^“he are entangled in each other, and irregular por- 
^ ns and veins of hard Limestone, with green grains and cretaceous 
SSI s, are here and there imbedded in the Granite. 
De la Beche. Geol. Manual. 3rd Edit. p. 296. 
