ADDENDA. (Add.) 



1. Skull of an adult Balcena biscayensis with the upper 



jaw highly arched. Length, condylo-premaxillary, in 

 straight line 13 feet 9 inches, over vertex 16 feet. 

 Greatest transverse diameter 9 feet 4 inches. Occipital 

 bone from foramen magnum to upper border 3 feet 

 9 inches, transverse diameter 3 feet 1 1 inches. Width 

 of hard palate from mesial ridge to lateral border 

 15 inches on each side. Foramen magnum 6 inches 

 in sagittal, and 5h inches in transverse diameter; 

 width across condyls 17 inches. Mandible without 

 coronoid process, length along outer curve 13 feet 

 6 inches ; girth in front of condyl 3 feet 7 inches. 

 Male, length of animal 51 feet, girth 32 feet. Caught 

 29th June 1912, 20 miles N.E. of St Kilda, by the 

 whaler " Sir Samuel Scott." 

 Donor, 1912— Mr Carl F. Herlofson, Tarbert, Harris. 



2. Tympano-periotic bones from the above skull. Right 



tympanic 5f inches long, 3| broad, 4| inches high ; 

 characters of tympanic and periotic as in No. 1, 

 page 30. Malleus and incus in situ. 



3. Heart and Great Vessels of Grampus griseus. The heart, 



as is customary in the Cetacea, is wide, 7f inches, in 

 relation to its vertical diameter, which is only 4^ 

 inches; the width greatly preponderates over the 

 height, and the apex is rounded. The trunk of the 

 pulmonary artery passes almost horizontally to the 

 left, and divides into right and left branches ; the 

 ductus arteriosus joins the descending part of the 

 arch of the aorta. The aorta arches to the left and 

 gives origin, close to the junction of the ascending 

 and transverse parts, to a right and a left innominate 

 artery. 



4. Tympanic Bulla. Fibro-mucous membrane which formed 



the pouch-like lining of the bulla of a whale. The 



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