29 
ON THE GENUS STEPHANOSAURUS, WITH A DESCRIPTION 
OF THE TYPE SPECIMEN OF LAM BEOS A UR US 
LAM BE I, PARKS 
DISCUSSION OF THE GENUS STEPHANOSAURUS 
In 1914, the late Lawrence M. Lambe proposed 1 the new genus Stephan- 
osaurus for reception of the species originally described 2 by him under the 
name of Trachodon marginatus. At the same time he described and figured 
the skull and jaws of a helmet-crested Hadrosaur which he referred to this 
species. In October of the same year Barnum Brown 8 , in a paper describ- 
ing the genus Corythosaurus casuarius, remarks that “It appears probable 
that this skull [Lambe’s Stephanosaurus] is congeneric with Corythosaurus 
casuarius, though clearly distinct as to species. That either is congeneric 
with the type of T. marginatus is improbable”. Subsequent discoveries 
showed that Brown was mistaken in the matter of the Stephanosaurus 
skull pertaining to the genus Corythosaurus , for in 1920 Lambe described 4 
and figured a second and more complete skull that clearly showed, so far as 
the referred skulls were concerned, that the genus Stephanosaurus was 
distinct generically from Corythosaurus. 
That Lambe was correct in referring the skulls to Stephanosaurus 
marginatus , however, has never been satisfactorily established, and the 
present paper is an attempt to straighten out this uncertainty. 
Brown 5 has given a concise review and discussion of the status of the 
type materials with which, after an examination of the original type 
materials and a full and careful review of the original and subsequent 
descriptions by Lambe, I fully concur. 
Brown says: “Lambe states (1914) that T. marginatus was based 
upon ‘a ramus of the lower jaw and a maxilla and the remains of one indivi- 
dual.' But reference to his original description (1902) shows clearly that 
the last-named specimen (consisting of humerus, radius, ulna, and some 
other parts named but not figured) was regarded as type at the time of 
description. It is first mentioned, and the describer goes on to say that 
4 the species is represented further by dissociated femora, tibiae, metacarpals, 
and phalanges of the manus, rami of the lower jaw and maxillae, dorsal and 
caudal vertebrae, a pubic bone, ischia, ilia, chevron bones, and numerous 
teeth, as well as other remains probably referable to the same species/ 
Whether the upper and lower jaws described by Mr. Lambe belonged to 
one individual has never been stated. The remains of the associated 
individual are then described and measured, and the descriptions of the 
femur, tibia, jaws, and other referred specimens follow. 
! Ottawa Naturalist, vol. 28, April, 1914, p. 17, PI. I. 
*Contr. to Can. Pal., vol. 3, pt. II, 1902, p. 71. 
‘Bull. Am. Mus. of Nat. Hist., vol. 33, October, 1914, p. 559. 
‘Geol. Surv., Can., Mem. 120, 1920, p. 74, Fig. 39 H. 
‘Bull. Am. Mus. of Nat. Hist., vol. 3, pt. II, 1902, pp. 559-560. 
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