200 MR ROBERT B. THOMSON : SCOTTISH NATIONAL ANTARCTIC EXPEDITION : 



Grey seal : 1 at C 7 D 15 L 5 S 3 Cd 12 . 



Bearded seal : 1 at C 7 D 15 L 5 S 3 Cd n . 



Northern fur seal : 1 at C 7 D 15 L 5 S 3 Cd 10 . 



Altogether 46 specimens with formula of C 7 D 15 L 5 S 3 Cd 10 to 12 . 



One specimen with formula of C 7 D u L 6 S 3 Cd n . 



The number of caudal vertebrae seems to vary from 10 to 12, while in some 

 cases one could not be positive, as frequently the terminal vertebrae are preserved 

 in the skins. 



SUPRA-CONDYLOID FORAMEN. 



With a view to the formation of a percentage of such foramina found in the humeri 

 of the Phocidse, I have examined altogether 100 humeri, made up as follows : — 



60 Weddell seals. 



4 crab-eating seals. 



6 leopard seals. 



4 sea-lions. 



2 Ross seals. 



4 elephant seals. 



4 South American fur seals. 



2 New Zealand fur seals. 



2 West Indian seals. 



2 common seals. 



2 North American fur seals. 



Total, 92 



In these 92 no foramen was present, but in 4 Weddell humeri there were small 

 supra-condyloid processes. 



In the following 8 humeri, supra-condyloid foramina were present : — 



2 grey seals. 



2 bearded seals. 



2 crested seals. 



2 common seals. 



Total, 8 

 thus giving a percentage of 8. 



Summary of Dentition. 



As the dentition of the Phocidse is of some importance, especially with regard to 

 variation, I have formed a table of the dentition of the seals under my observation. I 



