EXTINCT SPECIES. 121 



16. PAL^OTRHNTGA LITTORALIS Maksh. 



17. PAL^OTRIWGA VETUS Marsh. 



18. PAL^OTRIWGA VAGAWS Marsh. 



19. SULA LOXOSTYLA Cope. 



20. GRACULUS IDAHENSIS Marsh. 



21. GRACULAVUS VELOX Marsh. 



22. GRACULAVUS PUMILUS Marsh. 



23. GRACULAVUS ANCEPS Marsh. 

 23bis.* GRACULAVUS AGILIS Marsh. 



24. ICHTHYORNIS DISPAR Marsh. 

 24bis.t APATORNIS CELER Marsh. 



25. PUPFINUS CONRADI Marsh. 



26. CATARRACTES AK"TIQUUS Marsh. 



27. CATARRACTES AFPINIS Marsh. 



28. HESPERORWIS REGALIS Marsh. 



29. LAORNIS EDVARDSIANUS Maksh. 



*Not in the Key. (Marsh, Am. Joxir., Sci. and Arts, v, p. 230, March, 1873.) 



tNot In the Key. This species, with No. 24, represents a new order, IcJithyor- 

 nithes, of a new subclass, Odontornithes. (Marsh, Am. Jour., Sci. and Arts, v, 

 p. 161, Feb., 1873.) 



