PROF. CREPIN : CONSIDERATIOXS ON "SPECIES. 3G7 



oiir confidence in the results of M. Jordan's experiments, and those of his 

 followers, is far from perfect, since our own observations and those of the 

 partisans of the Linnean School lead to quite a different result. In our 

 opinion, the proofs to which the new creations have been submitted do 

 not constitute a veritable criterion. Are we deceived? Are the other 

 Linnean observers laboming under an illusion 1 AVe do not think 

 so, and therefore we must call in (|uestion the constant stability of the 

 multitude of forms described by jNI. Jordan. Had we experimented on 

 materials altogether similar to those of this gentleman, should we have 

 arrived at the same results as he has ? We cannot answer this question, for, 

 so far, we have not experimented on his identical forms. From the con- 

 tradictory facts we have established — from the uncertainty wliich the appli- 

 cation of the criterion of the new school entails — from the absence of a really 

 practical criterion in the old school, we cannot arrive, at present, at any 

 logical conclusion, either with regard to the new types or the old ones. 

 Nevertheless our own studies and observations, and perhaps also our pre- 

 judices, incline us to give the preference to the latter. It is possible that 

 some day we may have to acknowledge ourselves in error, and that facts may 

 compel us to rally on the side of those doctrines which we now combat. 



Let us noAv examine in more detail the manner in which the partisans 

 of the new school discriminate and delineate their sjDecies. In the first place, 

 they are led to recognise amongst the forms constituting the ancient types 

 several which may be easily distinguished, the one from the other, by an 

 assemblage of characters sufficiently marked and persistent. Little by little, 

 analysis pushed still further, the observations become more minute, and 

 they find that what they had taken for types — unities — are not such. As a 

 striking example of this subdivision, we may cite, 1st, the Erophila (jlahres- 

 cens of Pugillus, which becomes in the " Diagnoses " E. medioxina and E. 

 oblongata ; 2nd. Thlasj)i ijerfoliatitm of Pugillus, which is divided into T. 

 perfoliatum and T. martiale. These are however, the only two glaring 

 subdivisions in the " Diagnoses ;" but it is not improbable that after a succes- 

 sion of gropings, after many variations, the author of this volume has 

 finally amved at what he now considers as distinct types, or units. Has he 

 not oftentimes been led to subdivide what had at first appeared to him as 

 simple % He might, indeed, allow that he has groped, that what he had 

 believed to be simple, had after a more profound examination and better 

 conducted experiments, proved to be complex, but that this is only the 

 progression of all scientific research, and that we ought not to reproach him 



