PATAGONIAN EXPEDITIONS: PALEONTOLOGY. 



EXPLANATION OF PLATE LXVIII. 



PAGE 



Fig. i. PERIMYS IMPACTUS : Skull, base, X ^. No. 15,881. . . . 443 

 Fig. 10. " " Skull, top, X f No. 15,881. In both figures 



the rostrum is restored from a skull in the Ameghino collection. 

 Fig. 2. PERIMYS IMPACTUS : Right ramus mandibuli, side view, X ^. No. 



15.697 443 



Fig. 20. PERIMYS IMPACTUS : Right ramus mandibuli, crown view, X ^. No. 



I5.697- 

 Fig. 3. PERIMYS ONUSTUS : Right ramus mandibuli, side view, X ^. No. 



15,230 . . . . .44 2 



Fig. 30. PERIMYS ONUSTUS : Right ramus mandibuli, crown view, X -. No. 



15,230. 



Fig. 4. PERIMYS PUELLUS : Skull, left side, X -f . No. 15,284 . . . 445 

 Fig. 5. PERIMYS ERUTUS : Skull, base, X ^. No. 15,873 .... 439 

 Fig. 6. PERIMYS sp. : Left upper teeth, X ^. Ameghino collection. 

 Fig. 7. PERIMYS PROCERUS : Skull, base, X |. A. M. N. H. No. 9,507. 439 

 Fig. 8. PERIMYS ^MULUS, type : Right mandibular ramus, crown view, X y. 



Ameghino collection. ........ 448 



Fig. 9. PERIMYS IMPACTUS : Right mandibular ramus, side view, X $. No. 



15.053 443 



Fig. ga. PERIMYS IMPACTUS : Right mandibular ramus, crown view, X \. 



No. 15,053. 

 Fig. 10. PERIMYS AMEGHINOI, type: Left lower teeth, slightly less than 



natural size. Ameghino collection. ..... 444 



Fig. ii. PERIMYS PERPINGUIS : Right upper teeth, crown view, X ^. No. 



15,227 . 441 



Fig. 12. PERIMYS PERPINGUIS, type: Left lower teeth, crown view, X \. 



Ameghino collection . . . . . . . . 441 



Fig. 13. PERIMYS ERUTUS : Right lower teeth, crown view, X T . No. 15,105. 439 

 Fig. 14. PERIMYS SCALARIS, type: Right upper teeth, crown view, X ^. 



Ameghino collection ........ 440 



Fig. 15. PROLAGOSTOMUS PROFLUENS : Palate and teeth, X ^. A. M. N. H. 



No. 9,588 455 



Fig. 1 6. PROLAGOSTOMUS DIVISUS : Palate and teeth, X ^. No. 15,570 . 454 

 Fig. 1 7. PROLAGOSTOMUS PUSILLUS : Right upper teeth, crown view, X ^. 



Ameghino collection . . ' . . . . . 453 



Fig. 1 8. PROLAGOSTOMUS PROFLUENS : Right upper teeth, slightly less than 



natural size. Ameghino collection 455 



