BIRDS. 14<J 



lack the raeso-coracoid hook, or it is a mere rudiment ; the furcula has narrow and less curved 

 rami, and the inter-clavicle is very small. 



Example 2. Podiceps rubricollis, Gmel. 



The want of symmetry so frequently seen in the costal arches of Birds is well shown in this 

 species of Grebe. Plate XI, fig. 11, shows the last perfect sternal rib and part of the vertebral rib 

 of the left side (sr., v. r.) ; behind these is the first " floating rib ;" then comes an abdominal rib 

 (a.r. 1), which mounts up into the vertebral region, but without subdivision, and behind it there 

 is a smaller bar (a. r. 2), which is dilated above. On the right side (fig. 10) there is only one 

 abdominal rib (a. r.), which has, however, the rudiment of another near its upper end. I have 

 had these parts drawn on the same plate as those of the Chamaeleon, for the sake of comparison ; 

 the skeleton which shows them was made and drawn by me many years ago, and is now in the 

 Hunterian Museum. 



Family 



Example 1 . Phalacrocorax ? 



My young specimens of Pelecanine Birds 1 are from Guano, brought from the Chincha 

 Islands ; they are Cormorants and Boobies. The Shoulder-girdle and Sternum of the youngest 

 of the Cormorants is shown in Plate XIII, fig. 3 (natural size), as seen from below. 



The scapulae (sc.) are sword-shaped, straight, narrow most so at the middle, and pointed 

 at the ends; their supra-scapular end is soft, as is also the acromion and glenoid region (gl.). 

 The coracoids (cr.) are phalangiform rays with swollen heads and hooked (epicoracoid) bases ; these 

 are still soft, and so is the prse-coracoid bar (p. cr.) : this latter part is a large cartilaginous 

 wedge, with its flat end downwards, and its inner face in close contact with the clavicle (cl.). 

 This last is a sinuous, flexible rod, pointed above, then broader, and rounded below, where it 

 meets with its fellow, and forms a V-shaped " furcula," having a small inter-clavicle (i. cl.) at 

 their point of juncture behind : all these have already coalesced together. The Sternum has 

 acquired much of its permanent form, but it is still entirely unossified, and it has many embryonic 

 characters. The coracoid grooves (cr. g.) are wide apart, and there is no " rostrum " between 

 them ; the keel (k.) is small, thick, and undeveloped anteriorly, so that it does not reach nearly 

 to the front of the Sternum. The costal processes (c. p.) are short and rounded, they are fol- 

 lowed by five costal condyles for the sternal ribs (s. r.) ; the fifth of these is imperfect, and the 

 rib becomes a " floating " bar afterwards (it belongs to the second sacral vertebra), and is followed 

 by an abdominal rib ; they are almost entirely ossified already by ectostosis. The whole costal 

 region is one third longer than the xiphisternal, instead of being only two thirds, as in the adult ; 

 this latter part widens gently, and posteriorly, is elegantly crenate, and the points between the 

 shallow notches are the external (c. x.), the intermediate (i. x.), and the middle xiphoid (rn. x.) ; the 

 two latter do not reach quite so far backwards as the outer process. Altogether, the Sternum is 



1 The gift of T. J. Moore, Esq., of Liverpool. 



