236 ' ROYAL SOCIETY OF CANADA 
IPiAre a, 
Figure 1.—Left ramus of mandible of Leidyosuchus canadensis, exterior 
aspect; one-half natural size. Type of the genus. 
Figure 1a.—The same, viewed from within; one-half natural size. 
Figure 1b.—The anterior end of the same specimen as seen from above; 
natural size. 
Figure 2.—The anterior end of a right and sl gh‘ly larzer ramus, 
viewed from above; natural size. 
AN, angular; D, dentary; SA, surangular; SP, splenial; a, external 
mandibular foramen; ar, sutural surface for the articular; db. in‘ernal 
mandibular foramen; iii, viii, ix, xviii, alveolus for the third, eighth, 
ninth and eighteenth tooth respectively; dc, dental canal; dg. dentary 
groove; f, postsymphysial foramen; 0, opening in suture between splenial 
and dentary for passage forward of dentary (Meckelian) groove. 
