496 
THE GEOLOGIST. 
Certain horizontal areas, or provinces, have been characterized by the entire 
assemblage of animals and plants constituting their population, of which a con- 
siderable proportion is peculiar to each province, and the majority of each species 
have their areas of maximum development within it. 
Of the provinces of iVIarine Life, that much lamented, far-seeing, and genial 
philosopher, Edward Forbes, has provisionally defined 25. 
The same physical conditions are associated with a certain similarity between 
the animals of different provinces. Where those provinces are proximate, such 
lilceness is due to the identity or close affinity of the species ; but where the 
provinces are remote the resemblance is one of analogy, and species of different 
genera or families represent each other. 
A second mode of expressing the ascertained facts of the geographical distribu- 
tion of marine animals is by tracts called " Homoiozoic Belts," bounded by climatal 
lines ; which are not, however, parallel with lines of latitude, but undulate in 
subordination to climatal influences of warm or cold oceanic currents, relations of 
land to water, &c. Of these belts nine are defined ; one equatorial, with four to 
the north and four to the south, which are mutually representative. 
But the most interesting form of expression of the distribution of marine life is 
that which parallels the perpendicular distribution of plants, according to the 
depth at which they live, in a manner very analogous to the changes in the forms 
and species of vegetation observed in the ascent of a tropical mountain. Edward 
Forbes has expressed these facts by defining five bathymetrical zones, or belts of 
depth, which he calls, — 1, Littoral; 2, Circumlittoral; 3, Median; 4, Infra- 
median ; 5, Abyssal. 
The life-forms of these zones vary, of course, according to the nature of the 
sea-bottom ; and are modified by those primitive or creative laws that have caused 
representative species in distant localities under like physical conditions,— species 
related by analogy. 
Our space will not permit our proceeding step by step through this portion of 
the Professor's address, at any rate in this number, but the reference to the bear- 
ing of the ancient relations in geological eras of land and sea in the consideration 
of the question whether, and how many, distinct creations of plants and animals 
have taken place ? is too important a topic to be omitted. The discovery of two 
portions of the globe, of which the respective fauna and floree are different, by no 
means affords the requisite basis for concluding as to distinct acts of creation. 
Such conclusion, unconsciously associated with the idea of the historical date of 
creative acts, pre-supposes that the portion of the globe so investigated by the 
botanist and zoologist has been a separate creation — that its geographical limits 
are still in the main what they were when the creative fiat went forth. But 
geology has demonstrated that such is by no means the case ; the incalculable 
vistas of time past into which this science has thrown light are shown to have 
been periods during which the relative positions of land and sea have been ever 
changing ; and already the directions, and, to an extent, tlie forms of the submerged 
tracts that once joined what are now islands to the primeval continents, are 
beginning to be laid down on geological maps. 
'J'hese phenomena shake our confidence in the conclusion that the Apteryx of 
New Zealand and the Red-grouse of England were distinct creations in and for 
those islands respectively. Always, also, it may be well to bear in mind that 
by the word "creation," the zoologist means "a process he knows not what." 
Science has not ascertained the secondary causes that operated when the '■ earth 
brought forth grass and herb yielding seed after its kind," and when "the waters 
brought forth abundantly the moving creature that hath life." And supposing 
both the fact and the whole process of the so-called " spontaneous generation" of 
a fruit-bearing tree, or of a fish, were scientifically demonstrated, we should still 
retain as strongly the idea, which is the chief of the " mode " or " group of ideas " 
we call -'creation," viz., that the process was ordained by and had originated from 
an all-wise and powerful First Cause of all things. 
Remarks on .Sanitary Science, Agriculture, the Water-supply and Drainage of 
