130 CouES on the Burrowing OvjI. 



Fig. 3. The mandible, from above. 

 Fig. 4. The pelvis, from below. 

 Fig. 5. The sternum, from below. 



Fig. 6. Tran verse section of thorax, showing a dorsal vertebra, with 

 the con-esponding pair of ribs, and corresponding section of the sternum. 



Plate in. 



Vai'ious bones of the skeleton. 



Fig. 7. Anterior view of skull, the lower mandible having been re- 

 moved. 



Fig. 8. H, humerus ; i, ulnar tubercle ; i', oblique tubercle for radius 

 and ulna ; h, radial crest ; S A, S' A\ scapular arch ; S and S', scapula ; 

 C and C, clavicle ; Cr and Cr', coracoid ; /, perforating foramen. 



Fig. 9. H', humerus ; h", radial crest ; pf, pneumatic foramina ; S A" 

 and SA'", scapular arch; S" and S'", scapula; C" and C", clavicle; 

 Cr" and Cr'", coracoid ; /', perforating foramen. 



Fig. 10. HA, hyoid arch; a, superior view of atlas; a, the same 

 viewed laterally ; b, the axis ; o, its odontoid process. 



Fig. 11. Right carpus of Bitbo virfjimanns, outer aspect, with the 

 bones composing it moved partly from their normal positions to show 

 articulating surfaces ; rd, radius ; ul, ulna ; s, scaphoid ; c, cuneiform ; 

 in, metacarpus ; d, index digit. 



Fig. 12. Right radius and ulna, Speotyto, inner aspect; u, ulna; r, 

 radius; y, articular facet for oblique tubercle of humerus; v'j foi" "Inar 

 tubercle of humerus. 



; • Fig. 13. The same bones, inferior surface, when in position and the 

 wing closed ; r', radius ; u', ulna. 



Fig. 14. Posterior surface, right metacarpus. The differences in form 

 and position of such portion of the articular surface in the metacarpus as 

 is shown by z and z in Figs. 11 and 14 between Bubo and Speotyto are 

 here seen : flat and rounded below in the first, prominent and pointed in 

 the second. 



Fig. 15. Anterior surfaces, right tibia and fibula ; F, fibula ; T, tibia. 



Fig. 16. Posterior surfaces, same bones; F', fibula; T', tibia. 



Fig. 17. Right femur; v, posterior surface ; v, anterior surface. 



Fig. 18. Anterior surface, right tarso-metatarsus ; »n, bony bridge over 

 tendons ; j, foramen for anterior tibial artery ; e, facet for outer toe ; I, 

 for middle ; t, for inner toe. 



Fig. 19. Posterior surface of same bone ; f, the foramen for the anterior 

 tibial artery ; e", facet for outer toe ; l", for middle, and t" for inner toe ; 

 k, facet for os metatarsale accessorium. 



Fig. 20. A, right os metatarsale accessorium, superior surface ; B, base, 

 or inferior surface, of right tarso-metatarsus ; e, facet for outer toe ; i', for 

 middle, and t' for inner toe. The section of the shaft shows just above 

 the middle facet, on the posterior aspect, ranging near the middle third of 

 the bone. 



