Things are said to be named 'derivatively', which derive their name from some other name, but differ from
it in termination.
With these exceptions (and with that of the perfect fertility of varieties when crossed,--a subject hereafter to be discussed), domestic races of the same species differ from each other in the same manner as, only in most cases in a lesser degree than, do closely-allied species of the same genus in a state of nature.
Great as the differences are between the breeds of pigeons, I am fully convinced that the common opinion of naturalists is correct, namely, that all have descended from the rock-pigeon (Columba livia), including under this term several geographical races or sub-species, which differ from each other in the most trifling respects.
As, in an inquiry into every other subject, it is necessary to separate the different parts of which it is compounded, till we arrive at their first elements, which are the most minute parts thereof; so by the same proceeding we shall acquire a knowledge of the primary parts of a city and see wherein they differ from
each other, and whether the rules of art will give us any assistance in examining into each of these things which are mentioned.
In this it is supposed to differ from
the mind of animals.
Other factors may have been overlooked, but at present, says Strong, the message seems to be that the relative abundances of the elements simply differ from
one spectrum to the next.