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should we not plunge nomenclature if we were to adopt the practice 
of the learned Professor, instead of the precepts so judiciously laid 
down by himself and others of the Committee of Nomenclature of the 
British Association, and which I quote as a justification on my part 
for my refusal to adopt the learned Professor’s exchange of my name 
for the one he has proposed ! 
In page 4 of the Report, under the head of “ Law of Priority the 
only effectual and just one,” we find the following passages :—“ It 
being admitted on all hands that words are only the conventional 
signs of ideas, it is evident that language can only attain its end 
effectually by being permanently established and generally recog- 
nized. This consideration ought, it would seem, to have checked 
those who are continually attempting to subvert the established lan- 
guage by substituting terms of their own coinage.” ...... ** Now in 
zoology no one person can subsequently claim an authority equal to 
that possessed by the person who is the first to define a new genus 
or describe a new species; and hence it is that the name originally 
given, even though it be inferior in point of elegance or expressive- 
ness to those subsequently proposed, ought, as a general principle, to 
be permanently retained. To this consideration we ought to add the 
injustice of erasing the name originally selected by the person to whose 
labours we owe our first knowledge of the object.’ To these excel- 
lent principles the learned Professor has given the sanction of his 
signature. Prof. Owen, in the article on Pterodactylus in Mr. Dixon’s 
work, has not quoted my observations on those Reptiles so fully as I 
could have wished; inasmuch as he has adverted to the strongly- 
marked peculiarities of the bone-cells, which are the principal cha- 
racters in the question at issue, in so slight a manner, as almost to 
induce me to imagine that he must have forgotten them entirely. I 
shall simply content myself in challenging Prof. Owen to produce 
any such general structure and proportions of the bone-cells from the 
skeleton of any recent or extinct bird as those existing in the long bone 
described as Cimoliornis, or to produce any such radius and ulna of a 
bird containing similar bone-cells as those in the possession of Mrs. 
Smith, and figured by me in my paper in the ‘ Quarterly Journal of 
the Geological Society for February 1848,’ vol. iv. pl. 2- 
On the subject of the strictures with which Prof. Owen has fa- 
voured me at the conclusion of his observations in Mr. Dixon’s work, 
and how far I have been “wanting in a due comprehension of the 
subject, and have been a hindrance instead of a furtherance of true 
knowledge,” I am content to leave to the judgement of those who 
may feel a sufficient degree of interest to induce them to peruse what 
I have written in my former papers on the Pterodactyles of the Chalk. 
