96 



HADrvOSAURUS. 



The measurements of this bone arc as follows 



Extreme length .... 



Depth of shaft at middle . 

 Thickne.ss of shaft at middle 

 Height of tarsal extremity 

 Width of tarsal extremity- 

 Height of phalangial extremity 

 Breadth of phalangial extremity above 

 Breadth of phalangial extremity below 



Inches. 

 12 

 3 

 2 

 6 

 3 

 5 

 3 

 4 



Lines. 



3 



7 



6 

 9 

 1 



A proximal phalanx of the hind foot, represented in Figs. 11, 12, Plate XIV, is 

 the only bone of the toes preserved in the collection of Hadrosaurus remains. It 

 bears a near resemblance in size and general form and proportions with the corre- 

 sponding bone of the Igtianodon, as represented in Prof. Owen's Fig. 1, Plate XXI, 

 of the British Fossil Reptiles, Dinosauria. It is oblong square and moderately 

 expanded at the extremities. The proximal extremity, being the widest and 

 deepest portion of the bone, presents a reniform articular surface, which is in the 

 slightest degree concave. The distal extremity is deeply impressed at the sides for 

 ligamentous attachments. The articular surface is likewise reniform in outline, 

 vertically convex, and hardly depressed towards the median line. The measure- 

 ments of this bone are as follows : — 



Inches. Lines. 



Extreme length .......... 6 



Breadth at middle of shaft 3 9 



Height at middle of shaft ........ 2 4 



Breadth of proximal extremity 5 4 



Height of proximal extremity ........ 3 2 



Breadth of distal extremity ........ 4 5 



Height of distal extremity ........ 2 2 



Among the collection of Hadrosaurus remains are several bones whose position 

 in the skeleton I am unable positively to dejtermine. One of these, represented in 

 Figs. 4, 5, Plate XVII, most nearly resembles that indicated by Prof. Owen* and 

 Dr. MantelF as the ilium of the Icjuanodon. 



Assuming the bone to be a left ilium, it consists of a broad, thick plate, prolonged 

 into a long hook-like process, which curves backward and inward and is broken at 

 the extremity. The opposite extremity of the bone is likewise broken. The inner 

 border of the broad intermediate plate exhibits a long, ellipsoidal, irregular articular 

 surface for junction with the sacrum. From the outer border of the plate there 

 projects forward a massive trilateral tuberosity, roughened externally and at the 

 .summit, which probably corresponds ^vith the process projecting from the fore part 

 of the ilium in the Ljuana and Cyclura. The length of the specimen in its present 

 imperfect condition, measured in a straight line, is twenty-seven inches, and its 

 greatest breadth is nine inches and a quarter. The sacral articular surface is a 

 foot in length and about one-fourth that breadth. 



' British Fossil Reptiles, Dinosauria, Plates I and II. 



" Petrifactions and their Teachings, page 306, lignograph 65. 



