PATAGONIAN EXPEDITIONS: ZOOLOGY. 



EXPLANATION OF PLATE XXXIX. 



PAGE 



Figs. I, I a, \b. PoTAMOLiTHUS HiDALGOi Pils. Three views of type . . 597 



Figs. 2, 2a. PoTAMOLiTHUs iHERiNGi Pils. Two views of type . . 600 



PoTAMOLiTHUs jACUHYENSis Pils. Two views of type . . 583 



PoTAMOLiTHUS LAPiDUM (d'Orb.). Neanic Stage. Uruguay R. 587 



Adult " " 587 

 PoTAMOLiTiius SIMPLEX Pils. Two views of type . . . 578 

 POTAMOLITHUS LAPIDUM SUPERSULCATUS Pils. Front and pro- 

 file views ......... 588 



(vol. Ill) 



