106 PROCEEDINGS: BOSTON SOCIETY NATURAL HISTORY. 
between adjacent ranges and fronting on the sea; a theme which 
historians have often emphasized, although without giving much 
meaning to its fundamental features. The harborful coastline of 
northwestern Europe is, also, an illustration of a half-submerged 
topography. The sheltered waters of the numerous viks, or bays, 
developed a sea-faring people who impressed themselves most 
forcibly on early European history. The vik-ings, or bay people, 
were sea-kings through the growth of habits fostered by their 
geographical surroundings, but not through etymology. 
In our own country, we have numerous examples of drowned 
valleys, but none which so closely resemble the type form of the 
third model as do the rias on the mountainous coast of northwestern 
Spain. The ragged coast of Maine was not a mountainous country, 
but a dissected old-mountain peneplain, before its valleys were 
drowned by partial submergence. Moreover, a well-defined coastal 
plain of clayey and sandy strata containing marine shells occupies 
much of its littoral belt, and this proves that the region has today 
partly recovered from a greater submergence of a somewhat earlier 
time. The greater submergence allowed the sea to rise about three 
hundred feet above its present level, the shore line then being about 
as irregular as now. This submergence lasted long enough for the 
lone; arms of the sea to receive a considerable accumulation of sands 
and clays, by which the inequality of their floor was much reduced. 
The elevation by which the sand and clay deposits are in part 
revealed still allowed the sea to occupy various valleys between 
projecting headlands and outstanding islands; hence the irregular 
shore line of today. The elevation occurred only long enough ago 
to permit the extended streams to cut narrow valleys in the plain. 
In the t}q)ical coastal plain of the second model, the old and the 
new shore lines are comparatively straight and lie nearly parallel to 
each other. The coastal plain of Maine is a most irregular patch- 
work, without regularity of inner or outer margin. It penetrates 
far inland between rocky hills and ridges that were once promon¬ 
tories ; it wraps around rocky knobs that were once islands. So 
open is the suggestion of the rocky ledges which often rise through 
the fiat clay fields, that the farmers (who have often had a turn at 
sea-faring) call them “reefs.” The discontinuity of the plain is so 
great that it is seldom recognized in geographical descriptions. Yet 
once seen and appreciated as a coastal plain formed along a ragged 
instead of along a smooth coast, its essential peculiarities may be 
