APPENDIX. 



Art. XLV. — Principal Characters of American Jurassic 

 Dinosaurs. Part IX. The Skull and Dermal Armor of 

 titegosaurus : by O. C. Marsh. (With Plates VI, VII, 

 VIII, and IX.) 



In previous numbers of this Journal, the writer has given 

 the more important characters of the skeleton of the Etego- 

 sauria, and has indicated the relations of this group to the 

 other known Dinosauria* The discovery of additional speci- 

 mens of Stegosaurus, one of them nearly complete, furnishes 

 material to greatly enlarge our knowledge of the skull and 

 dermal covering of this genus, and some of the new facts are 

 placed on record in the present article. 



The results of the entire investigation of this group will be 

 brought together in a monograph how in preparation, by the 

 writer, for the U. S. Geological Smwey. The lithographic 

 plates for this volume, sixty-five in number, are nearly all 

 printed, and the figures of the skull here given are taken from 

 these plates. 



* This Journal, vol. xiv, p. 513, Dec, 1877 ; vol. xix, p. 253, March, 

 1880; vol. xxi, p. 167, Feb., 1881; and vol. xxiii, p. 83, Jan., 1882. 



Am. Jour. Sci.— Third Series, Vol. XXXIV, No. 203.— Nov., 1887. 

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