Osteological Studies of the Sub-Family Ardeince . n 
portion, whose relations are to be described below, is horizontally 
flattened, though not very broad. 
Several years ago Professor Parker found a “ post maxillary” 
in the Emu, and subsequently discovered a similar segment in 
several of the Herons, as Ardea garzetta , Nycticorax ardeola , and 
in the Bitterns, as Bo/aurus viridis , and B. stellaris. 
This postmax illary is said to be situated or found behind the 
angle of the maxillary. I find no such bone in the specimens of 
Herons before me, and can add nothing to the words of Professor 
Parker given above. It nay be that the postmaxillary is present 
in Ardea herodias , but so far absorbed in the adult as not to be 
recognized, or if a free bone, it has undoubtedly been lost, as my 
specimens have been in my collection for several years. In either 
case, fresh material in the flesh, both young and adult, would be 
required, for me to examine and decide upon such a point. 
The quadrate of the Blue Heron is a large and massive bone, 
and indeed, such is its character in all of the Ardince so far exam¬ 
ined by me. Its head presents for our examination two distinct 
and elongated articular facets, separated by an abrupt and squar¬ 
ish notch. These facets occupy the inner and outer borders of 
the head of the bone, with their long axis parallel to the long- 
axis of the skull ; the outer one, which at the same time is slightly 
the larger, is in advance of the inner, a circumstance which makes 
it rather appear that this end of the quadrate was obliquely twist¬ 
ed. Anteriorly, the bone develops a broad lamelliform orbital 
process, which is flattened behind and convex forwards in front, 
and gently curved throughout, to the same degree as the posterior 
wall of the orbit behind it, though it does not touch the latter. 
The apex of this orbital process of the quadrate is nicely 
rounded off, and the anterior surface immediately below its border 
looks almost directly forwards, a difficult thing to show in a 
drawing (Figs. 2 and 3). 
Posteriorly, the shaft of the quadrate is pierced by a large 
pneumatic foramen, sufficiently large to permit one to see the tra¬ 
becula spanning its hollow interior, from wall to wall. The 
massive foot of this bone presents for examination six articular 
facets. 1. Upon the lateral aspect the usual cup, for the ball and 
socket joint with the quadrato-jugal. 2. O11 the extreme outer 
side of jthe inferior surface, a sub-elliptical facet, separated from 
the remaining four by a deep valley. This facet is the largest of 
