EXPLAXATKJX OF PI.ATIi CI\'. 



]\IoUTONICICRAS DHI.AUAKKXSIS ( MiiTtrjll ) ]j. 8.17 



1-3. Lateral, ventral and Jnr.sal \ie\vs ut an incuniplete internal 

 cast. 



Mi'rch:iiil;'illL chiy-iinnl : Lciinhi. (iCs). 

 4-5. Lateral and ilur.^al \ie\vs i.if the tx'fie specimen. 

 Mci'chdiif-z'illi' clay-iiui li. 



Pl.ACF.NTICEKAS PLACENTA ( DeKaV ) p. S3O 



6. Lateral \'iew of an incomplete internal cast of an immature 

 specimen, 



Ulcrchaiilz'illc chiy-inarl ; l.cin'li). (r6s). 



Pi,,\CF.N'rici:RA,s TELirrR ( ilorton ) p, 8,12 



/-S. Views of two lr;i;4"ments used by Mortnu in ids descrif)- 

 tion fif the species. 



Locality not kimzcii. 



1092 



