EXPLANATION OF PLATE XLII. 



Fio. 1. Maxillary and palatine arches of Portheua lestrio, from Trego County, Kansas: displaying the 



premaxillary, maxillary, ethmoid, prefrontal, sclerotic, palatine, malleolus, ectopterygoid, 



pterygoid, and metaptcrygoid bones. One-half uatural size. 

 2. Lower part of scapula, with adjacent parts of clavicle ; the former with inferior articulation of 



pectoral spine ; one-half natural size. 

 ■I. Upper part of the same scapula, showing two superior articular facets and two posterior fossas 



for basilar bones. 



4. External view of the pectoral spine and rays, and scapula of Pori7ie«s-like Saurodont, the artic- 



ulation slightly dislocated to show the three facets ; one-third natural size. 



5. Internal view of the inferior part of the scapular arch of an allied species, exhibiting the scap- 



ula and coracoid and foramen inclosed by them, the three facets, and two cotyli ; one-half 

 natural size. 



6. Ajysopelijc sauriformis, Cope, type-specimen from Brookeville, Kansas. 



7. Tooth of Encltodus gladiolus, natural size; a, section of base, natural size. 



8. Scales of a Clasles, from the Milk River, Saskatchewan, natural size; a, edge-view. 

 Figs. 9-10. Lamna macrorhiza, Cope, from Kooks County, Kansas; uatural size. 



11-12. Lamna mudgci, Cope. 



