X48 Zoological Society : — 



So we see that the birds with nails in their wings are (with one 

 or two exceptions) all aquatic types, the more unspecialized forms of 

 which are for the most part possessed of dorsal vertebrae conjomed 

 by a cup-and-ball (opisthocoelian) articulation, and are very far below 

 the typical tree-birds in their structure and in their habits. 



But the digit-claws appear in other birds which have not out- 

 standing spurs. Professor Owen {ibid. p. 39) mentions the Apteryx 

 has having the mid digit terminating in a joint, which supports a 

 curved claw ; the Emeu and the Cassowary have the same structure ; 

 and the Rhea has an ungual j)halanx covered with a claw added to 

 the index-finger, which is generally composed of one joint in birds. 

 The Swan, as well as the Chaja {Palmnedea), have the same, and they 

 both have the mid-finger series complete, the last joint being most 

 perfect in the Swan {Cyynus olor). The furculum of the Palamedea 

 is more Uke that of that great pluvialine the Bustard {Otis tarda) 

 than that of a Goose ; but it is very much more solid : its only coun- 

 terpart for relative size is that of the Archceopteryx. The coracoids 

 are strong bony tubes, open below by a large scooped hollow. The 

 sternum of this bird differs from that of the Goose or Swan by jus,t 

 so much as the sternum of the Short-winged Kails, especially Bra- 

 chypteryx, differs from that of the ordinary types. It is narrower 

 behind, and the episternum is gone from the front : yet it is tho- 

 roughly anserine in character, for the keel does not reach the end ; 

 and, indeed, it is in this respect intermediate between what we see in 

 the Geese and what occurs in the "Totipalmatse." Eight ribs reach 

 the sternum by hsemapophyses, as in the Swan ; there are seven in 

 the Goose, Psophia, and Serass Crane. On the right side there are 

 a pair of floating hsemapophyses (reptilian), and these answer to the 

 fourth and fifth so-called sacral vertebrae. In the Swan these h?ema- 

 pophyses are better developed, and the penultimate has a long rib 

 reaching it from the sacrum on both sides. And this brings me to 

 say that the sacrum in birds, although actually of great length, has 

 superadded to it a number of dorso-lumbar vertebrae in front, and 

 often several true caudals behind. 



Professor Owen {ibid. pi. 3. fig. 5) makes the first postfemoral 

 joint in the young Ostrich to be the first true caudal. I cannot 

 agree with him here ; for I think that the sacrum in birds is long 

 as a prolepsis of that of the mammal, but that it is an exaggeration 

 of the mammalian sacrum. In the Archceopteryx there are four 

 vertebrae behind the acetabula before we come to those marked caudal 

 by Professor Owen {ibid. pi. 4. fig. 1 c, d). This has led me to 

 run over the birds' pelves in my own collection and drawings ; and 

 the following table, which gives the number of vertebrae, closely 

 embraced and tied together by the extension backwards of the iliac 

 bones behind the acetabula, in different birds, is the result of my 

 observations. I shall remark upon the bearings of these facts after- 

 wards. 



