8 



The Naturalist. 



readily distinguished and defined ; that hard and fast lines of distinc- 

 tion and definition can be made, which are true and exact in every 

 particular, and are thus the true exponents of Nature. 



To all these statements I fearlessly and strongly give a complete 

 denial, inasmuch as they are not the true expression of what we find in 

 Nature. I must, then, attempt to make it clear to you why I dissent 

 from these opinions, which after all were, until very recent years, 

 accepted as correct. 



So long ago as 1864, M. A. Jordan, of Lyons, a French botanist of 

 no mean repute, published a work, the English translation of the title 

 of which is " Diagnosis of New or Misunderstood Species," in which 

 he endeavoured to show — and with some fair reasoning, too — that an 

 immense number of what had hitherto been considered good species of 

 plants, after the Linnean type, were in reality not species, but groups 

 of species. In the x)reface to this work (p. 7) he states that all his 

 proposed new species are really nothing more than certain vegetable 

 forms " (previously united under one specific name) " which he had 

 learned to distinguish from the others by comparisons on the living 

 plants, of all their organs " ; and he had established, by most certain 

 observations, that their differences were hereditary, and could not be 

 attributed to accidental or local causes. And this, he says, is true of 

 the vast majority of our species. He further states that he has 

 arrived at these conclusions only after a course of study and 

 experiment, extending ov^er twenty-five years, during which time he 

 has grown and re-grown the various forms which he terms species, 

 without ever finding them either to intermix or revert to what might 

 be called their original type. With M. Jordan, every slight difference, 

 if reproduced by seed during a number of years, such as say the 

 hairiness or otherwise of a leaf, a slight difference in the size or shape 

 of a seed-vessel, or a leaf of the calyx, and so forth, is sufiicient to 

 constitute a species. In this manner he makes out of our usually 

 accepted Anemone Pulsatilla four species ; of Ran. acris he makes six 

 species (one of which, R. tomophyllus, seems really a good one) ; of 

 Papaver Rhoeas he makes eight, of Arahis hirsuta he makes twelve, 

 and of Draha verna 53. But few of these so-called species were ever 

 recognised at all by other botanists, and what few were recognised 

 were merely held as varieties. 



This is Jordan's idea of a species, and a most comprehensive one it 

 is. He belongs to the school called " splitters," and he is a " splitter" 

 of a most advanced type ! 



In the "Naturalist" for 1865, M. F. Crepin, a Belgian botanist. 



