

Parr V. Scr. ii. §1.] RECENT OR HUMAN PERIOD. 901 
the valleys in the'drift-covered parts of North America, as in the similar 
regions of Europe. Sometimes four or five platforms, the highest being 
a hundred feet or more above the present level of the sea, may be seen 
a above each other, as in the well-known example of the Connecticut 
alley. 
The terraces are not, however, confined to river-valleys, but may be 
traced round many lakes. Thus in the basin of Lake Huron deposits of 
fine sand and clay containing fresh-water shells rise to a height of 
40 feet or more above the present level of the water, and run back from 
the shore sometimes for 20 miles. Regular terraces, corresponding to 
former water-levels of the lake, run for miles along the shores at heights 
of 120, 150, and 200 feet. Shingle beaches and mounds or ridges, exactly 
like those now in course of formation along the exposed shores of Lake 
Huron, can be recognized at heights of 60, 70, and 100 feet. Unfossili- 
ferous terraces occur abundantly on the margin of Lake Superior. At 
one point mentioned by Logan, no fewer than seven of these ancient 
beaches occur at intervals up to a height of 331 feet above the present 
level of the lake.t The great abundance of terraces of fluviatile, lacus- 
trine, and marine origin led, as already stated, to the use of the term 
“Terrace Epoch” as the designation of the time when these remarkable 
topographical features were produced. 
India.—There is abundant evidence that at a late geological period 
glaciers descended from the southern slopes of the Himalaya Mountains 
to a height of less than 3000 feet above the present sea-level. Large 
moraines are found in many valleys of Sikkim and Eastern Nepal be- 
tween 7000 and 8000 feet, and even down to 5000 feet, above sea-level. 
In the Western Himalayas perched blocks are found at 3000 feet, and in 
the Upper Punjaub very large erratics have been observed at still lower 
elevations. No traces of glaciation have been detected in Southern India. 
Besides the physical evidence of refrigeration, the present facies and dis- 
tribution of the flora and fauna on the south side of the Himalaya chain 
suggest the influence of a former cold period.” 
New Zealand.—tThe present glaciers of the New Zealand Alps had 
a much greater extension at a recent geological period. According to 
Dr. Haast they descended into the plains, and, on the west side of the 
island, probably advanced into the sea, for along that coast-line their 
moraines now reach the sea-margin ; huge erratics stand up among the 
waves, and the surf breaks far outside the shore-line, probably upon a 
seaward extension of the moraines.* Captain Hutton, however, points 
out that there is no evidence from the fauna of any gencral and serious 
refrigeration of the climate during this glacier period.* 
Section II.—Recent or Human Period, 
§ 1. General Characters. 
The long succession of Pleistocene ages shaded without abrupt 
change of any kind into what is termed the Human or Recent 
1 Geology of Canada, p. 910. 
2 Medlicott and Blanford, Geology of India, p. 586. 
3 Geology of Canterbury and Westland, p. 371. 
4 Geology of Otago, p. 83. 
