PLATE LX. 



Fig. 



Fig. 

 Fig. 



Fig. 

 Fig. 

 Fig. 

 Fig. 



Ug. 



m. 

 mp. 



n. 

 o. 



P- 

 pal. 



Ligament between 



lower jaw. 

 Maxillary. 

 Metapterygoid. 

 Nasal. 

 Operculum. 

 Parietal. 

 Palatine. 

 paro. Paroccipital. 

 po. Alisphenoid. 

 pi: Prasoperculum 

 pf. Pterotic. 

 (J. Quadrate. 

 r. Rostrale. 

 »'f. Scapula. 

 .id. Supraclavicle. 

 so. Suboperculum. 

 spo. Supraoccipitnl 

 sq. Squamosal. 

 sy. Sympleotic. 

 V. Vomer. 



the ectopterygoid and 



Figs. 1-8. Skull oi Halosaurus macrochir (page 233). 



1. Lateral view of the skull with the infraorbital chain and other superficial bones. 



2. Lateral view of the skull with the superficial bones removed. 



3. Upper view of the skull, with the lateral membrane bones removed on the left 

 side. 



4. Anterior part of the snout, upper view ; twice natural size. 



5. Lower view of the cranium. 



6. Anterior part of the snout, lower view ; twice natural size. 



7. Side view of the cranium. 



Fig. 8. Occipital view ; enlarged. 



a. Facet for the articulation of hyomandibular. 

 an. Anterior nasal. 

 h. Basal. 

 bo. Basioccipital. 

 d. Clavicle. 

 CO. Coracoid. 



ep. Lateral prworbital process of primordial 

 cartilage. 

 e. Groove of the transverse process of the eth- 

 moidal medium. 

 ec. Anterior termination of ethmoid cartilage. 

 ecp. Ectopterygoid. 



pcp'. Condyle of the ethmoid cartilage for the 

 articulation of the ectopterygoid. 

 em, em'. Ethmoidale medium. 

 ep. Entopterygoid. 

 e.ro. Exoccipital. 

 /nil. Hyomandibular. 



/. Frontal. 

 im. Intermaxillary. 

 io. Interoperculum. 



9. 

 10. 

 11. 

 12. 

 13. 

 14. 



Fig. 

 Fig. 

 Fig. 

 Fig. 



Fig- 

 Fig. 

 Fig. 15 



b. 



bo. 

 br. 

 d. 



CO. 

 PC. 



ecp. 



em. 



ep. 



.f. 



hm. 



im. 



Figs. 9-15. Skull oi Noiacanthus s;exspinis 



Lateral view of the skull. 



Lateral view of the cranium. 



Upper view of the cranium. 



Lower view of the cranium. 



Palatal arch with suspensorium and lower jaw ; twice natural size. 



Back view of cranium ; twice natural size. 



Front view of snout : t-wace natural size. 



Basal. 



Basioccipital. 



Branchiostegals. 



Clavicle. 



Coracoid. 



Ethmoidal cartilage. 



Ectopterygoid. 



Ethmoidal? medium. 



Entopterygoid. 



Frontal. 



Hyomandibulare. 



Intermaxillary. 

 io. Interoperculum. 

 m. Maxillary. 

 n. Nodule of cartilage. 



1>- 

 pal. 



po. 



Operculum. 

 Parietal. 

 Palatine. 

 Alisphenoid. 



jn-. Praeoperculum. 



'/. Quadrate. 



r. Kostrale, with r 



■■ic. Scapula. 

 xcl. Supraclavicle. 



so. Suboperculum. 

 spo. Supraoccipital. 



■it. Stylohyal. 

 ■11/. Symplectic. 

 uh. Urohyal. 



its cartilaginous portion. 



