1882.] MR. W. A. FORBKS ON THE GENUS ORTHONYX. 545 



In Orthony.v ochrocephala the left carotid retains its normal sit- 

 uation, though the point of entrance into the canal is somewhat 

 higher up than is usual in other Passeres. 



Examination of my spirit-specimens of these two birds has con- 

 vinced me that the two forms are not really congeneric, the New- 

 Zealand bird (O. ochrocepliala) differing from the Australian in its 

 more slender bill, less development of the nasal operculum, less 

 spiny tail, and more slender claws. The coloration of the two forms 

 is quite unlike ; whilst internally the skull and syrinx exhibit dif- 

 ferences, slight in amount, but greater than those usually Ibinid in 

 birds of the same genus. Under these circumstances it seems that 

 Clitomjx of Reichenbach ' will be the correct generic term for the 

 New-Zealand birds, as Lesson's name Mohoua, though of prior appli- 

 cation", is not only barbarous but, what is more important, liable to be 

 confounded with Mohoa, also a genus of Passeres from the Pacific 

 Subregiou. 



In the present unsatisfactory condition of the systematic grouping 

 oftheOscinine Passeres, it is impossible for me to point out clearly an; 

 definite position either for Orthonyx or Clitomjx, though both forms 

 might, I apprehend, be safely placed in Mr. Sharpe's somewhat 

 vaguely-defined " Timeliidfe." 



The determination of the not-intimate relation of Orthonyx to 

 Clitonyx is a point of some importance, from its bearing on the 

 question of the general relationships of the fauna of New Zealand 

 to that of Australia, Orthonyx having been sometimes mentioned 

 as one of the few peculiar Australian genera of birds also repre- 

 sented in the satellite island ^. 



I may take this opportunity of stating that I have, in the course of 

 the last few months, been enabled to examine examples of several 

 genera of Passeres the condition of the syrinx in which has not before, 

 I believe, been recorded. These include, of Old-World forms, Hi- 

 mator, Ptencedus, Sphenura, Sphenostoina, Climacteris, Creation, 

 Miro, Certhiparus, Petrceca, Entomyza, Poinarea, PhoRornis, Fal- 

 cunculus, Nesocich/a, Nesospiza, Cracticus ; and of American forms, 

 Chamcfa, Du/us, Phainopepla, Ptilogonys. In all these genera the 

 syrinx is perfectly Osciuine, as indeed was to be expected from the 

 external structure of the birds. Johannes Miiiler at first placed 

 Ptilogonys amongst the Tnannidfe'*, misled by the slightly aberrant 

 structure of its tarsus, but on subsequently examining the nearly 

 allied Myiadestes, and ascei taining its Oscinine nature, concluded that 

 Ptilogonys too would, on examination, be found to have the muscular 

 organs of voice ^ a surmise the correctness of which is now demon- 

 strated. Petrceca has been stated by Prof. Parker^ to be a " Tra- 



' Haiidb. Spec. Oriiith. p. Ifi7 (1851). 

 ^ Hist. Natur. Oiseaux, iii. p. 189 (1837). 



3 Wallace, ' Geogr. Distribution of Animals,' i. p. 451 ; but see also ' Island 

 Life,' p. 45y, footuote. 



* Vocal Organs of Passeres, Garrod's ed. p. 41. 



* L.c. p. (il. 



" Trans. Z. 8. ix. p. 3.3C>. 



