“Tree-Ducks” of the genus Dendrocygna. - 69 
Pilates 
: 'Fig.. 93. Right lateral view of the skull and detached mandible 
of a specimen of .Charitonetta albeola. Natural size. Adult. Coll. U. S. 
Nation. Mus. No. 17168. The thecae of the mandibles left on in part. 
'Fig. 94. Left lateral view of the skull and detached mandible 
of a.Scaup Duck (Marila marila). Adult; nat. size (No 19220a, Coll: 
U. S. Nation. Mus.). 
Fig.. 95. Right lateral view of the trunk skeleton, including 
bones of the shoulder girdle of a specimen of Hymenolaemus mala- 
corhynchus (New Zealand). Slightly reduced. Adult, @ (No. 19024, Coll. 
U. S. Nation. Mus.). Note small proportions of the os furcula, and 
the shallow keel to the sternum. 
Fig. 96. Left lateral view of the trunk skeleton including 
shoulder girdle of Cereopsis novae-hollandiae. Two-thirds natural size 
(No. 19711, Coll. U. S. Nation. Mus... Pygostyle proportionately very 
small; scapulae short; pelvis large and strong. 
Plate 13. 
Fig. 97. Dorsal aspect of the trunk skeleton and articulated 
shoulder girdle of the Cereopsis goose (O. novae-hollandiae). Same 
as the one shown in Fig. 96, Pl. 12. About two-thirds natural size. 
Fig. 98. Anterior view of the trunk skeleton of a specimen of a 
Wood Duck (Aix sponsa) (No. 18612, Coll. U. S. Nation. Mus.). Shows 
the pattern of the large sternum in this species of River Duck (see 
Fig. 99). 
Fig. 99. Left lateral view of the trunk skeleton of Aix sponsa. 
About natural size. Adult (No. 18612, Coll. U. S. Nation. Mus.). Shoulder 
girdle removed. Note large sternum and massive caudal skeleton. 
Plate 14. 
Fig. 100. Left lateral view of the trunk skeleton of Polystieta 
stelleri. Adult; nat. size. Shoulder girdle removed (No. 15272, Coll. 
U. S. Nation. Mus.). See former figures. 
Fig. 101. Ventral view of the sternum of a specimen of Aix 
galericulata. Very slightly reduced (No. 18217, Coll. U. S. Nation. Mus.). 
See Plate 11 Fig. 84 and 85. 
Fig. 102. Ventral view of the sternum of a specimen of Harelda 
hyemaliıs. Very slightly reduced (No. 18627, Coll. U. S. Nation. Mus.). 
See Plate 9 Fig. 64. 
Fig. 103. Ventral view of the sternum of a specimen of Dendro- 
eygna autumnalis, 2. Nearly natural size. Collected by Mr. F. B. Arm- 
STRONG, Browsville, Texas (454). 
