XXXV111 INTRODUCTION. 



with a list of plants observed by Professor C. C. Babington in 

 Pembrokeshire. In such cases as these, it would assuredly be 

 most unwise to forego the advantage of citing good personal 

 authorities for the county habitats, and on no better reason 

 than the mere fact that they had already appeared in some 

 journal or other book; the addition of which to their names, 

 with volume and page also specially shewn, would require a full 

 half line or upwards, instead of the quarter line or less here 

 actually available. The individual personal authority being the 

 one essential matter, those compiled lists which have been 

 founded on the joint testimony of several different botanists, 

 whether printed or still in manuscript alone, obviously cannot 

 be quoted. Unfortunately, the compiler has grounds for 

 suspecting that the distinction here specified has not been 

 always strictly adhered to by the makers of the local lists 

 themselves ; who appear in some very few of the lists to have 

 entered plants on hearsay testimony, or even on supposition 

 only, and yet entered them as if certainly seen. He has 

 absolutely rejected three marked catalogues on their internal 

 evidences of this deception or carelessness; and of course the 

 markers were deeply offended. 



If a botanical correspondent should deem his name erro- 

 neously quoted for any county and plant, it is requested that 

 he will at once point out and correct the error. This should be 

 done, whether the error may have arisen through a mistake by 

 the compiler, or through an inadvertence in the original note or 

 label or list of plants sent to him. Failing any indication to 

 the contrary, the compiler must himself be held responsible for 

 the nomenclature (sp.) of the plants ; the more so, because the 

 names on labels have been altered occasionally by his own 

 hand; so that a collector may find himself here credited for 

 a species different from the one supposed to have been sent. 

 Such cases will be the exceptional few ; although the writer's 

 own experience and opportunities have told him that not any 

 botanist, who labels much, will entirely avoid occasional mis- 

 takes and inadvertences in writing the names of plants. 



