...definition of species which science can adopt is one which implies no theory. He considers a species " an assemblage of individuals which resemble each other...directly or indirectly, to produce fertile individuals, which do not (as far as human observation goes) give rise to individuals which vary from the general...

...exactly similar to one another, is at best but a probability, and is in no case capable of proof. Tpon the whole, then, it seems in the meanwhile safest...therefore, may be defined as an assemblage of individuals ichich resemble each other in their essential characters, are able, directly or indirectly, to produce...

...can be entertained but that the individuals of species universally admitted to be distinct arecapable of mutual fertilisation ; the hybrid progeny thus...assemblage of individuals which resemble each other in tluir essential characters, are able, directly or indirectly, to p'uduce fertile individuals, and which...

...pairs exactly similar to one another, is at best but a probability, and is in no case capable of proof. Upon the whole, then, it seems in the meanwhile safest...or indirectly, to produce fertile individuals, and ivhich do not (as far as human observation noes) give rise to individuals ichich vary from the general...

...pairs exactly similar to one another, is at best but a probability, and is in no case capable of proof. Upon the whole, then, it seems in the meanwhile safest...of individuals which resemble each other in their essentml characters, are able, directly or indirectly, to produce fertile individuals, and which do...