I do not know who first emphasized the need for a clear understanding of the sense in which the term species is to be applied. In the second half of the seventeenth century Ray shows some degree of concern on this matter. In the introduction to the Historia Plantarum, 1686, he discusses some of the difficulties and lays down the principle that varieties which can be produced from the seed of the same plant are to be regarded as belonging to one species, being, I believe, the first to suggest this definition.
William Bateson, Problems in Genetics (1913).
He that useth many words for the explaining any subject, doth, like the cuttle fish, hide himself for the most part in his own ink.John Ray
The Wisdom of God Manifested in the Works of the Creation.John Ray
Beauty is power; a smile is its sword.John Ray
There are two thousand of them constantly gliding back and forth through the canals, as noiseless as a ghost and as graceful as a swan .John Ray