Plate XXIV. 



Figure 1. Adjacent ends of metacarpal V and the first phalanx of the left wing of 

 Pteranodon sp., No. 2628 ; ulnar side, x 0.50 



Figure 2. The same specimen ; radial side, x 0.50 



Figure 3. Adjacent ends of metacarpal V and the first phalanx of the left wing of 

 P. occidentalis Marsh, No. 1165 (identification of O. C. M.). at the angle of ex- 

 treme flexure ; ulnar side, x 0.50 



Figure 4. The same specimen ; radial side, x 0.50 



Figure 5. Conjoined fragments of the left metacarpal V and the first phalanx of Pteran- 

 odon sp., No. 2660 ; palmar surface, x 0.67 



Figure 6. The same fragments separated ; palmar surface, x 0.67 



