VOLCANOES 3381 
While there are many regions in which volcanoes 
are now, or have recently been active in great numbers, 
Fie. 197. 
Diagrammatic sketch to show (by dots) distribution of volcanoes. 
there are other areas, such as the main portion of the 
Mississippi valley, from the base of the Appalachians 
| > sae 
Fic. 198. 
Popocatepetl, Mexico, a voleano of perfect form which has not been in eruption 
this century, and is either dormant or extinct. 
