514 
PACIFIC SCIENCE, Vol. XV, October 1961 
FlG. 25. Diagrammatic representation of regions of marine habitat (modified after Ekman, 1935). 
stratum is apparent not only geographically in 
the area but also vertically. In the deeper water 
soft mud bottoms predominate but sand and 
gravel are also found, and in the shallower areas 
sand, mud, gravel, pebbles, boulders, and solid 
rock are all found to varying extent, particularly 
along the Vancouver I. side of the Strait. In 
the shallower regions, however, a solid rock or 
bouldery substratum predominates. The nature 
of this rocky substratum in Queen Charlotte 
Strait is equally varied. There are igneous as 
well as sedimentary and metamorphosed sub- 
strata. There are basalts, dolerites, trachytic 
rocks, hard sandstones or quartzites, shales, con- 
glomerates, argillites, fine-grained to crystalline, 
commonly cherty limestones mixed with feld- 
spathic rocks, and dioritic and granitic frag- 
ments are also common. 
The preceding brief summary of the general 
geological features of the area indicates the 
present status of published knowledge (Bo- 
stock, 1948; Dawson, 1880, 1881*, 1881 b, 1888, 
1897) concerning the Queen Charlotte Strait 
region. 
Bottom Topography of Queen Charlotte Strait 
Although soundings are still incomplete for 
the area, a study of the bottom topography ( Fig. 
2) in Queen Charlotte Strait indicates exten- 
sive shallows, particularly along the Vancouver 
I. side of the Strait and around Malcolm I. 
In this region an abundant and varied inter- 
tidal and subtidal flora and fauna are supported. 
In the central part of the Strait and between 
Nigei and Vancouver islands (Fig. 2), there 
are deeper channels exceeding 100 fathoms. The 
water in these deeper channels is not continu- 
ous, however, with the deep waters of the main- 
