456 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 52 



EXPLANATION OF PLATES 



Plate XLIII 



Fig. I. — Proinia patagonica, new species. No. 15459, Princeton Univ. Coll. 

 Type skull. Patagonian beds, Darwin Station, Santa Cruz Terr., 

 Patagonia. Collected by J. B. Hatcher, April 24, 1899. 

 Superior surface. About ^ natural size. 

 Fig. 2. — Prosqualodon australis Lydekker. No. 15441, Princeton Univ. Coll. 

 Portion of right ramus of mandible. Patagonian beds, San Julian, 

 Santa Cruz Terr., Patagonia. Collected by J. B. Hatcher, April 

 22, 1899. 



External surface. About yi natural size. 



Plate XLIV 



Teeth of Prosqualodon australis Lydekker. No. 15441. 

 Fig. I. — Root of an upper incisor. 

 Fig. 2. — A right upper incisor. Inner surface. 



Fig. 3. — A right upper premolar. Inner surface, showing three roots. 

 Fig. 4. — Left posterior upper molar? Outer surface. 

 Figs. 5 and 6. — Right lower incisors. Inner surface. 

 Fig. 7. — Right lower canine or premolar? Inner surface. 

 Fig. 8. — A right lower molar. Outer surface. 

 Natural size. 



Plate XLV 



Vertebrae of Prosqualodon australis Lydekker. No. 15441. 

 Fig. I. — Atlas. Anterior surface. 

 Fig. 2. — The same. Right side. 

 Fig. 3. — Thoracic vertebra. Anterior surface. 

 Fig. 4. — The same. Right side. 



Fig. 5. — Another thoracic vertebra. Anterior surface. 

 Fig. 6. — The same. Right side. 



One-half natural size. 



