Geology and Falueotitology. l<ji> 
Vertebrata of that country and Asia. Four families have disappeared 
since that epoch, viz.: The Glyptodontidse, Megatheriidae, Elephant- 
idae and Eschatiidae. The genus Holomeniscus has passed away. 
The disproportion of extinct forms increases as we go south. Thus 
in the Oregon beds we find that out of twenty-six determined 
species, ten are still living. With further examination this list will be 
probably increased. At the Texan and Mexican localities no re- 
cent species have been yet determined. As we enter the South 
American extension of the same fauna, the number of extinct species 
and genera greatly increases, although some recent species have 
been found associated with them in the Pampean Fauna. 
I have found Indian implements in considerable numbers in such 
close proximity to the fossils of the Oregon Desert, as to lead to the 
strong suspicion that they are contemporary with the latter. This 
opinion has been, according to Mr. G. K. Gilbert, reduced to cer- 
tainty by the finding of such implements in place in the Equus 
beds in Nevada or California. The age of the Equus beds is placed 
by Mr. Gilbert as Plistocene (Quaternary.) 
The Neighborhood of Seville.— The city of Seville is situated 
in the alluvial plain of the Guadalquivir, which every few 
years, at the height of the winter rains, rises sufficiently high 
to flood the streets. On both sides of these alluvial flats is a 
nto the clayey hills ; this is succeeded by a 
southeast of the river, between it and the 
are secondary rocks, among which the Nummulitic and Jurassic 
have been recognized. Between the folds of these rocks are inter- 
calated series of more or less metamorphosed rocks, which were re- 
garded by Sr. Macpherson as Triassic, but which Sr. Calderon, from 
the discovery of fossils still remaining in them, has proved to be 
altered Nummulitic or Jurassic strata, according to their position. 
On the opposite side of the river there exists a Triassic area, but the 
greater part of the formations are either Palaeozoic or eruptive. 
Granites, gneiss, syenite, diorite, diabase, and porphyry cover exten- 
sive areas, there are patches of Carboniferous strata, and a consider- 
able extent of Cambrian. 
At Penaflar, a few miles above Seville, the mountains (Sierra 
Morena) come near to the river, and in the hollows are deposits of 
gold-bearing clay, which is supposed to be derived from the diorite 
and diabase above, though it is mingled with material from the 
archaic limestone and mica-schists. A section at this spot shows the 
limestone interrupted by two broad bands of diorite, also with lines 
of phosphorites, a thin vein of magnetic iron, and two bands of 
mica-schists. _ Near the Guadalquivir there is a great fault, which 
brings the Miocene suddenly to the surface. The upper portion of 
the Miocene is conglomerate, the lower molasse. Two wide bands 
of amphibolite intersect the Miocene. On the south of the Guadal- 
