178 Transactions. — Zoology. 



here, so that such bones of this kind as are present can be 

 identified with ahnost absolute certainty as being those of 

 Aptornis, and, as I have before said, can by their pecuharities 

 be allotted to definite individual skeletons. As ■svill be seen 

 from the table of measurements, the dimensions of the limbs 

 agree very closely v^ith the measurements given by Owen 

 (p. 315, op. cit.), but the individual distinguished as B is 

 slightly larger in all its measurements. '■'■ It is just possible 

 that it may be found that this represents the species provision- 

 ally named by Professor Owen A. hulleri, in a letter to Sir 

 Walter Buller, quoted at p. xxii. of the introduction to Buller's 

 "Birds of New Zealand" (new edition). I am at present, 

 however, inclined to regard the difference as due to sex. 



The Skull. — Apparently the first Aptornis skull received 

 by Professor Owen was a very fine specimen of the smaller 

 species in Mr. Mantell's collection in 1848, and for a time 

 it figured as the skull of Dinornis casuarinus ; but in a paper 

 in the Philosophical Transactions of the Eoyal Society of 

 London, 1866, the late Professor "W. K. Parker wrote very 

 fully on the essentially Ealline characters presented by the 

 skull, which he incidentally calls " nearly as precious and 

 quite as unique as the skeleton of the ArchcBopteryx," and he 

 goes on to say that in his opinion the skull has great affinities 

 with Psophia, the trumpeter crane, specially drawing attention 

 to the greatly-developed basi-temporal pterygoid processes, 

 the decurved lower mandible, and the almost complete ossifica- 

 tion of the interorbital septum. Professor Parker considered 

 the bird a Notornis, and proposed the name of JSlotoriiis 

 casuarhms for it. 



For his work on the "Extinct Birds of New Zealand," 

 Professor Owen was fortunate enough to receive a beautiful 

 skull of Aptornis defossor from Oamaru, and it is excellently 

 figured in plates Ixxxiii. and Ixxxiv. of that work. 



The collection obtained by Mr. Mitchell contained one 

 skull which is absolutely perfect, and three others more or 

 less damaged. There are three lower maxillaries. 



The Vertebra. — At present I have only been able to select 

 one complete set of the vertebrae. Fortunately, one atlas 

 vertebra occurred, and, on comparing it with the three or 

 four specimens of the axis vertebra, one was found to fit it 

 exactly. Thus an important part, and one often missing 

 from fossil skeletons, is now known. The cervical vertebras 

 immediately succeeding the axis rapidly increase in size, and 



* I have given the measurements in decimal notation, as being more 

 generally useful than inches and lines or tenths. Some of the slight dif- 

 ferences may be accounted for by the system of measurement adopted. 

 All my measurements are made on the lines of major axis of the bones, 

 or at points at right angles to it. 



