L'12 Annals of the Carnegie Museum. 



least vertically in N'. 7i. ncez'iiis). As a negative character we find 

 ihe mandible in all Ardeime without a ramal vacuity. 



19. There are 44 vertebrre and a pygostyle in the vertebral column 

 of the Ardeina. In all, the dorsal series are free ; in all, the twenty- 

 fourth to the thirty-seventh inclusive are anchylosed with the pejvic 

 bones ; in all there are seven caudals. In Ardea the eighteenth and 

 nineteenth vertebrae bear free ribs, and all seven caudal vertebrae are 

 free. In Nycticorax violaceiis the seventeenth, eighteenth and nine- 

 teenth vertebrae bear free ribs, and the anterior caudal vertebra an- 

 chyloses with the sacrum. "WiO. pygostyle is comparatively small. The 

 epipleural appendages of the ribs are small and free. 



20. Sternum of good size ; its manubrium prominently developed ; 

 broadly 2-notched ; four articular facets on either side for costal ribs ; 

 carina rather deep, its lower border convex and nearly the arc of a 

 circle ; dorsal aspect very concave ; coracoidal grooves decussate ; cos- 

 tal processes broad ; one large pneumatic foramen in the median line 

 above, just over anterior border. 



21. Coracoid and scapula non-pneumatic ; coracoid very broad be- 

 low, antero-posteriorly ; compressed from side to side above ; scapular 

 process small ; slight differences in the two bones, at their sternal ends, 

 due to their crossing each other. Scapula broad anteriorly, much 

 compressed from above, downwards ; apex rounded ; blade rather long, 

 not truncate, but tapers gradually to the end. Furcula non-pneumatic ; 

 upper half of each limb convex anteriorly, the reverse below ; when 

 articulated with coracoid, nearly reaches the scapula at the inner an- 

 terior angle of its head ; hypocleidium has a superior and an inferior 

 process. 



22. Pelvis is rather massive ; pre- and postacetabular surfaces about 

 ec]ual; ischiac foramen large ; obturator foramen opens largely into ob- 

 turator space ; ilio-neural grooves sealed over anteriorly ; one pair of 

 free ribs articulate with the pelvis. 



23. The humerus is the only pneumatic bone of the pectoral limb, 

 the periphery of the orifice being in the general surface ; remainder 

 of limb well proportioned. Bones of pelvic extremity long and 

 straight-shafted, except the iibula, which is short. In Ardea the fibula 

 is short and free below. In Nyeticorax violaeeus fibula long and an- 

 chylosed with tibio-tarsus below. 



24. Tendinal osseous bridge at lower end of tibio-tarsus exists and 

 is thrown nearly square across the groove. 



