A. EF. Verrill—The Bermuda Islands; Geology. 143 
just alike. Some of the most abundant species of small shells com- 
monly found are shown on plate xxiv, figures 1, 2. 
In the channels and passages between the islands, and especially 
on shallow bars, where there are active currents and wave action, 
the fine calcareous ooze is washed away more or less completely and~ 
the bottom usually consists, in such places, of nearly clean shell-sand, 
which may contain numerous living and dead foraminifera, amount- 
ing, in some cases, to 10 or even 20 per cent., while in the immediate 
37b 
Figure 37a.—Stichopus Moébii, spotted variety, ventral side, + natural size. 
Figure 37b.—The same, dorsal side. Drawn from life by A. H. Verrill. 
vicinity of reefs the fragments of calcareous algze may sometimes 
amount to 25 per cent. or more, and in such places the fragments of 
Millepora, Oculina, ete., may rise to 20 per cent. or more, in some 
instances. 
In the sheltered harbors and more or less enclosed lagoons, espe- 
cially in the deeper parts, where there is but little wave action, the 
fine ooze that is washed out from other places settles down and 
forms a soft, more or less coherent, whitish, grayish, or yellowish 
