108 



DINOCERATA. 



The pyramidal bone in a second specimen of Dinocems, and in one 

 of Tinoceras, is shown in figures 117 and 118, below. 



Figure 111. — Left |.yramidal of Tinoceras ingens, Marsh (No. 1577); distal end. 

 Figure 118.— Left pyramidal of Dtnoce/'as mw-afti'k, Marsh (No. 1230); distal end. 

 mcY. face for fifth metacarpal; un. face for unciform. 



Both figures are one-half natural size. 



The following' are tlie more important dimensions of the jjyramidal 

 bone in three specimens of Binoceras and Tinoceras : 



Measweiiients of Left Pyramldnl. (Dinoceras inivabile. No. 1208.) 



m. 



Greatest length of longitudinal axis of pyr;iinid;il, .. .045 



Total length of bone, .098 



Least transverse diameter, .054 



Greatest diameter of ulnar articular surface, — — .073 



Antero-posterior diameter of ulnar articular surface, . . . .049 



Greatest diameter of articular face for unciform, 004 



Antero-posterior diameter of articular face for unciform, .05 1 



Diameters of face for fifth metacarpal, 01 8-.0'29 



Measurements of Left Pijraniidal. (^Dinoceras minihile, No. 1230.) 



m. 



Greatest length of longitudinal axis of pyramidal, - 042 



Greatest diameter of bone, -100 



Least transverse diameter, -- -062 



Greatest diameter of ulnar articular face, _ . _ _ . .083 



Antero-posterior diameter of ulnar articular face, __. .'49 



Greatest diameter of face for unciform, .067 



Antero-posterior diameter of face for r.m-iform, .••57 



Diameter of face for fifth metacarpal, _ 020 



