214 Transactions . — Zoology. 



brown, and tliere is less of the buff and rufous stains wliicli impart so warm 

 an effect to the breast of //. novce-zealandice. Tliere are other ruinute points 

 of difference, but these may be mere individual peculiarities. Enough has, 

 however, been pointed out to show that the two species may be readily 

 distinguished from each other ; and this is the only point at issue. 



Of course the w^hole value of this evidence depends on the accuracy of 

 the " sexing" in each case. I think this, however, is placed beyond all doubt, 

 for the larger bird was determined by Mr. J. D. Enys, who collected it, 

 while the smaller one was received at the Museum in the flesh, and was 

 dissected by the taxidermist for the express purpose of ascertaining the sex. 

 Mr. Fuller assures me that he was most careful in his examination, and that 

 the specimen exhibited is to an absolute certainty a female. 



In his last paper on the Birds of New Zealand (Trans. N. Z. Inst., Vol. 

 VI., pp. 139-152) Mr. Potts enters upon this question, and in doing so takes 

 occasion to contrast what I said in 1868 with what I said on the same subject 

 in 1872. His argument is somewhat obscure; but if he simply means that I 

 am open to conviction where I find myself wrong, I readily concede the point. 

 But the inconsistency to which he directs attention is more apparent than 

 real. Hieracidea hrunnea Gould (=11. ferox^ Peale) was originally described 

 from an immature bird. The observations recorded in my early paper have 

 at any rate proved useful as evidence that the plumage of the young is alike 

 in both species. However, I am glad to find so good an observer as Mr. 

 Potts in favour of there being two species, because it tends to confirm my 

 present belief. 



Art. XXV. — Notes on an alleged new Slides of Tern (Sterna alba. Potts). 

 By Walter L. Buller, D.Sc, F.L.S., C.M.Z.S. 



[Bead before the Philoso'phkal Institute of Canterhwij, 1st October, 1874.] 



Mr. Potts, in his notes on the birds of New Zealand read before the 

 Philosophical Institute of Canterbury in December last (Trans. N.Z. Inst., 

 Vol. VI., pp. 139-153), takes exception in the following terms to my treat- 

 ment of his supposed new species of Tern, {Sterna alba) : — 



" The white Tern seen by the writer on the Ashburton, and described by 

 him in Trans. N. Z. Inst., Vol. III., is quietly placed by Dr. Buller with 

 *S'. nereis, to which ho gives the name of the Little White Tern. This fine 

 white Tern was seen on the Waitangi Biver by the Hon. G. Buckley and 

 others. Last month (20th November) a pair were seen flying up and down 

 the course of that great river." 



