19 
can alone be determined by the acquisition of more complete speci- 
mens of the animal than those at present known. 
In the construction of this table I have taken the proportions of 
P. longirostris as the foundation, as it is the only species from which 
I could get the measurements of all the bones of the wing from the 
same animal; but it must not be supposed that the restorations 
effected in the table will be absolutely correct at all times in its appli- 
cation, for we see that in P. longirostris the radius and first pha- 
lange are equal, but in erassirostris and Bucklandi this is not the 
case: the greatest discrepancy rests with erassirostris, while Buck- 
landi and brevirostris accord much more nearly with the proportions 
of longirostris ; and if we may judge by the comparative difference 
between those bones in Jongirostris on the one part, and Bucklandi 
and crassirostris on the other, it may perhaps be fairly surmised that 
the greater length of wing would be found to exist in the long-nosed 
species, and consequently that Bucklandi will prove to belong to the 
short-nosed ones; and this also would seem to be indicated by what 
remains of the cervical vertebre in the original specimen in the Bri- 
tish Museum. 
Prof. Owen, in treating of these animals in my late friend Mr. 
Dixon’s work ‘On the Geology and Fossils of the Tertiary and Cre- 
taceous Formations of Sussex,’ has thought proper to re-name P. gi- 
ganteus, and designate it P. conirostris, Owen. I certainly did not 
lend my specimens to my late friend Mr. Dixon for the illustration 
of his work, with a view of having the name which I had assigned to 
this new and gigantic species subverted, and without in the slightest 
degree being consulted on the subject. Nor can I concur with the 
reasons given by Prof. Owen for thus re-naming it, as the name gi- 
ganteus was not given, as stated by the learned Professor, “‘ because 
certain bones of another and larger animal, of a different species, have 
been erroneously referred to it ;” but, in truth, from its being the 
largest distinct species at that time known, exceeding P. Bucklandi 
(or Macronyzx) by two feet in the spread of its wings, and P. grandis 
of Cuvier by above a foot. The beautiful specimen of radius and 
ulna in the possession of Mrs. Smith, and subsequently figured in my 
second paper, was at that time unknown to me, and the bone then in 
the possession of the Earl of Enniskillen was claimed by the Professor 
as that ofa bird. I had therefore no other material than that in my 
own possession on which to base my name of giganteus. 
If the learned Professor’s reason for the proposed change of name 
is to hold good, that of exclusive fitness in specific nomenclature, then 
the one he proposes is also inappropriate, as it might be with equal 
propriety given to either crassirostris or brevirostris; or if specific 
names, based on comparisons of size, are to be extinguished, and new 
names given on the discovery of new species, there would be no end 
of the confusion generated ; thus, as P. brevirostris is thicker in its 
proportions than erassirostris, they would require to exchange names, 
or the latter at least to be re-named ; medius would no longer be me- 
dius, with the addition of our new species, and grandis would no longer 
be grand in comparison. Into what an unenviable state of confusion 
