EXPLANATION OF THE PLATES. 



PLATE I. 

 Illustrates a paper by Dr. George Johnston, on a Whale stranded near Berwick upon Tweed, 



Article III. page 6. 



PLATES II. III. IV. 

 Illustrate Mr. Buddie's Notice of a Whin Dyke in Benwell Colliery, Article IV. page 9. 

 PLATE II. — Section of the Whin Dyke in the Fenham Division of Benwell Colliery. 

 PLATE III. — Diagram to illustrate the supposed undulating structure of the Whin Dyke, taken in the line of 



its direction from Coley Hill to Simonside. 

 PLATE IV.— Plan of Benwell Colliery, shewing the course of the 90- Fathom Dyke, and the Whin Dyke 



lately discovered, &c. 



PLATES V. VI. VII. 

 Illustrate Mr. Selby's Observations on the New Species of Swan, &c., Article V. page 17. 



PLATE V. — Fig. 1. — Sternum of old Cygnus Bewickii, shewing the horizontal loop which the trachea describes 



at the posterior extremity of the excavation. 

 Fig. 3.— Trachea and sternum of female Ct/gniu Bewickii (Haydon Bridge specimen), shewing 



the commencement of the horizontal loop or curve which the trachea assumes at the 



extremity of the cavity. 

 Fig. 3.— Sternum and lower part of the trachea with the inferior larynx or bone of divarication 



and bronchial tubes of Cygnus Bewickii. 

 PLATE VI — Fig. 1. — Sternum and trachea of Cygnus ferus, shewing the vertical bend which it takes within 



the excavation, which excavation does not extend to the bottom or posterior parts of 



the keel. 

 Fig. 2.^Lower portion of the trachea and inferior larynx of Cygnus ferus, shewing its position on 



the ridge of the sternum, with the bronchial tubes attached to it. 

 Fig. 3. — Ridge of keel of Cygnus Jerus, 

 Fig, 4. — Ridge of keel of Cygnus Bewickii, 

 Fig, 5. — Inferior larynx of Cygnus Bewickii, as seen from above. 

 Fig. 6.— Inferior larynx of Cygnus ferus. 

 Fig, 7. — Side view of the inferior larynx of Cygnus ferus. 

 Fig, 8.— Side view of Cygnus Bewickii, 



