MOXODOX. 99 



13. Non-protruded tooth of the Narwhal, 7| inches long; 



spiral arrangement not developed, free end pointed, 

 opposite end 1 inch wide, hollowed as if it had lodged 

 a large dentar papilla. 



Donor— Prof. W. C. M'Intosh, F.R.S. 



14. Tympano-periotic bones, left, articulated, of an adult ; 



length of tjanpanic bulla 2| inches, breadth 1 inch, 

 height ^ inch ; outer and inner surfaces with deep 

 indentation ; inferior surface two-lobed posteriorly, 

 separated by a wide deep cleft ; outer lobe smooth, 

 rounded, much more prominent than inner, blends 

 with outer surface ; inner lobe continuous with strong 

 ridge which separates inner from inferior surface ; 

 cavity opens by wide mouth close to anterior end 

 of this surface. Surface in front of cleft rough. 

 (Figure of inferior surface below.) Periotic 2^ inches 



Ion Of, 1| inch broad ; meatus wide. 



Turner Collection. 



15. Tympano-periotic bones, left, of a foetus, fused ; tympanic 



bone 1;^ inch long; chain of tympanic ossicles m 

 sUu. Turner Collection. 



16. Sternum of an adult, length 12 inches, breadth of manu- 



brium 11 inches. A round mesial foramen lies between 

 the second and third segments ; articulations for five 

 pairs of ribs. Deep presternal notch. 



Goodsir Collection. 



17. Pectoral Limb of Narwhal, right ; humerus 5f inches long, 



radius 4| inches, ulna 5| inches; epiphyses fused. 

 Carpus with radiale, r, intermedium, i, ulnare, u ; the 

 intermedium has fused with it a nodule which may 

 be an os centrale ; C^, C2+3 and C3+4 are distinct 

 bones. The digits are MPhg for pollex, j^, MPh^, 

 MPh^, MPho, MPh2, minimus, V. Radiogram on page 

 100. " " Struthers Collection. 



