104 BULLETIN 89, UNITED STATES NATIONAL MUSEUM. 



been referred to this genus, ten of which are American and four European. Of 

 these, one appears to be a nomeii nudum, one is a synonym of a species alreadv 

 described, and three others have been referred to other genera. Now only nine 

 valid species are recognized, and a revision of these will probably bring about a 

 further reduction. 



An alphabetical list of the species, location of the type, and its catalogue num- 

 ber is given below: 



Stegosaurus affinis Marsh, 18S1 (nomen nudum) (Yale University Museum). 



Stegosaums annatus Marsh, Dec, 1877 (No. 1850, Yale University Museum). 



Stegosaurus (Onwsaurus) armatus (Owen), 1876 (No. 46013, British Museum) =Dacenirurus annatus 

 (Owen). 



Stegosaurus (Hypsiropkus) discurus (Cope), Mar., 1878 (Amer. Mus. Nat. Hist.). 



Stegosaurus duplex Marsh, Nov., 1887 (No. 1858, Yale University Museum) =S. ungulatus. 



Stegosaurus durobrivensis Hulke (British Museum). 



Stegosaurus (Onwsaurus) hastiger (Owen), 1877 (Nos. 46320, 46321, 46322, British Museum) =Dacen- 

 trurus hastiger (Owen). 



Stegosaurus longispinus Gilmore, 1914 (No. D54, Univ. of Wyo.). 



Stegosaurus marshi Lucas, Feb., 1901 (No. 4752, U. S. Nat. ~M\is.)=Hoplitosaurus marshi (Lucas). 



Stegosaurus priscus Nopcsa, Mar., 1911 (No. R, 3167, British Museum). 



Stegosaurus (Hypsiropkus) seeleyanus (Cope), June, 1S79 (Amer. Mus. Nat. Hist.). 



Stegosaurus stenops Marsh, Nov., 1887 (No. 4934, U. S. Nat. Mus.). 



Stegosaurus sulcatus Marsh, Nov., 1S87 (No. 4937, U. S. Nat. Mus.). 



Stegosaurus ungulatus Marsh, Dec, 1879 (No. 1853-1858, Yale Univ. Museum). 



Description of Species. 



"With one exception the following descriptions are based on type-specimens in 

 the United States National Museum. The reference to the original description is 

 followed by citations of the more important literature which further elucidates the 

 species under consideration. 



The parts of the skeleton constituting the type are listed, and the locality, 

 geological horizon, name of the collector, and catalogue number are given in each 

 case, so that a permanent record of the type material will hereafter be available. 



In the discussion of the species the original description will be quoted in its 

 entirety, followed by a historical account of the specimen and a further description 

 of such parts of the skeleton as seems necessary to supplement the original text. 



STEGOSAURUS STENOPS Marsh. 



Plates 2-9 and 11-17, 19; 22, fig. 3; 23, figs. 2, 3, 4, 6; 24. 



Stegosaurus stenops Marsh, Amer. Journ. Sci. (3), vol. 34, 1887, pp. 414, 415, pi. 6; Geol. Mag. (3), 

 vol. 5, 18S8, pp. 11-15, pi. 1. — Ltdekker, Cat. of Fossil Reptilia and Amphibia in the British 

 Museum, pt. 1, 18S8, p. 176, fig. 31. — Zittel, Handbuch der Palaeontologie, vol. 1, 1890, p. 

 745, figs. 650, 654.— Marsh, Amer. Journ. Sci (3), vol. 39, 1890, p. 426, pi. 7, fig. 2; vol. 42, 

 1S91, p. 179. — Cope, Trans. Amer. Philos. Soc, vol. 17, 1892, p. IS (Hypsiropkus ).— Marsh, 

 16th Ann. Rept. U. S. Geol. Surv., pt. 1, 1896, p. 186, pis. 43 and 47, fig. 3; Mon. 27, U. S. 

 Geol. Surv., 1897, p. 499, fig. 52.— Woodward, Outlines of Vertebrate Paleontology, 1898, p. 

 212, fig. 131.— Nopcsa, Foldtani KozlQny, Budapest, vol. 31, 1901, p. 215.— Hat, Bull. 179, 

 U. S. Geol. Survey, 1901, p. 496.— Lull, Amer. Journ. Sci., vol. 29, 1910, pp. 206, 208; vol. 30, 

 1910, p. 373; Verhandlungen des VIII. Internationalen Zoologen-Kongresses zu Graz, 1910, 

 p. 677. — Zittel, Grundzuge der Palaeontologie, pt. 2, 1911, p. 293, fig. 442. — Huene, Neues 

 Jahrbuch, vol. 37, 1914, pp. 5S0, pi. 10. 



Diracodon laticeps Marsh, Amer. Journ. Sci., vol. 24, 18S7, p. 416, pi. 9; Geol. Mag. (3), 1888, pp. 11-15, 

 pi. 3 ; 16th Ann. Rept, U. S. Geol. Surv., pt. 1, 1S96, p. 193, pi. 51. (Not D. laticeps Marsh, 1881.) 



