148 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 vertebree conjoined 
by a cup-and-ball (opisthoccelian) 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 (247d. 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 phalanx 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 (Pa/amedea), have the same, and they 
both have the mid-finger series complete, the last joint being most 
perfect in the Swan (Cygnus olor). The furculum of the Palamedea 
is more like 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 Archeopteryr. 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 just 
so much as the sternum of the Short-winged Rails, 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 “ Totipalmatz.’’ Eight ribs reach 
the sternum by heemapophyses, as in the Swan; there are seven in 
the Goose, Psophia, and Serass Crane. On the right side there are 
a pair of floating heemapophyses (reptilian), and these answer to the 
fourth and fifth so-called sacral vertebree. Inthe Swan these hzema- 
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 vertebre in front, and 
often several true caudals behind. 
Professor Owen (did. pl. 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 Archeopteryx there are four 
vertebrze behind the acetabula before we come to those marked caudal 
by Professor Owen (cdid. pl. 4. fig. 1 ec, 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 vertebre, 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, 
