

infests the Lombardy- Poplar. 145 



have been published to the world in a manner in no 

 degree calculated to make impressions favourable to the 

 original writer. In giving the opinions of others, it is 

 always becoming and modest to do it in their own words. 

 Had this been done in the present case, I flatter myself 

 that I should not now feel any necessity of writing in the 

 language of explanation. 



From this, I hope, there will be no inference unfa- 

 vourable to Dr. Vaughan's candour. The Doctor had 

 not the authority alluded to, and, being under the per- 

 suasion, that all Caterpillars must end in butterflies, he 

 hastily wrote, what I am happy to believe, his real sen- 

 timents. 



But, at best, whatever may relate to the genus of the 

 animal can be viewed as no part of the main point ; it 

 only came in by the way, in the rank of a probability. 

 The sole object of the experiments was to ascertain 

 whether the reptile possessed qualities hostile to animal 

 life, and Dr. Vaughan has determined them to prepon- 

 derate on the negative scale. 



The Doctor may have knowledge of experiments 

 which have not fallen under my notice. Of such I can 

 say nothing, nor from such can I admit any thing, except 

 they were of public notoriety, and subscribed by a respon- 

 sible name. As to experiments, anonymous, or signed 

 by fictitious characters, they certainly cannot be brought 

 into account. Where there is no responsibility, there 

 can be no authority. But even were negative experi- 

 ments admitted, they carry nothing beyond probability, 



