Anatomy of Acanthidositta chloris. 621 



several distinct systems of arrangement — Garrod, Forbes, 

 Sclater, Salvin and Godman, Sharpe, and Gadow being 

 among the most notable contributors. Each, in attempting 

 to solve the riddle, has arrived at a separate solution ! 



In that vast treasure-house, the British Museum of 

 Natural History, much new material has collected, and this 

 I hope to draw upon in attacking the problem afresh. 



References. 



i. Beddard, F. E. — Structure and Classification of Birds. 



z. Forbes, W. A. — Contributions to the Anatomy of Passerine Birds. — 

 Part VI. On Xenicus and Acanthisitta as Types of a new Family 

 (Xenicidte) of Mesomyodian Passeres from New Zealand. P. Z. S. 

 1882. 



3. Gadow, H. — Bronn's Thier-Reichs (Vogel). Band 6. Systematische 



Theil. 



4. Garrod, A. H. — On some Anatomical Characters which bear upon 



the Major Divisions of the Passerine Birds : Part I. P. Z. S. 1876. 



5. Muller, J. — On certain Variations in the Vocal Organs of the 



Passeres. Engl. Transl., F. J. Bell, 1878. 



6. Sclater, P. L. — Remarks on the present State of the Systema 



Avium, Ibis, 1880. 



7. Sharpe, R. B. — A Review of Recent Attempts to Classify Birds. 



1891. 



EXPLANATION OF PLATE XIII. 



Fig. 1. Skull of Acanthidositta chloris, side view to shew the po.^t- 

 orbital region, schizorhinal nares. 

 1 a. The same skull, to shew the palate. 

 lb. The same skull, top view, to shew the form of the nares. 

 Fig. 2. Skull of Pitta baudi, side view, to shew the postorbital region 

 for comparison with the skull of Acanthidositta. 

 2a. The same skull, top view, to shew the form of the nares. 

 Fig. 3. The skull of Synallaxis cegithaloides, side view, to shew the 

 schizorhinal nares. 

 3a. The same skull, to shew the form of the palate. 

 35. The same skull, top view, to shew the form of the nares. 

 Fig. 4. The pterygopalatine articulation of Acanthidositta. 

 Fig. 5. The pterygopalatine articulation of Pitta for comparison with 

 that of Acanthidositta. 



SER. VIII. — VOL. V. 2 T 



