6 
Osteological Studies of the Sub-Family Ardeincz. 
ap eciated by comparing the lateral aspects of the skulls of the 
tw birds. Figs, i and 28. 
I omitted to point out in passing the difference between the 
B 1 • Heron and Nycticorax violaceus in so far as the cranio-facial 
re; )n is concerned, as seen upon this view. Referring to Fig. 29, 
wt vill see that the transverse depression described for the Blue 
H' 311 is not present in the Yellow-Crowned Heron, the region in 
th atter being occupied by a shallow concavity. The articula- 
tic is quite free, however, in the dried skull, and the relations of 
tin nesethmoid are about the same as in the Blue Heron. 
The skeleton of Nycticorax violaceus that I am using, is not 
th of an adult bird—it being “a bird of the year,” which I 
co cted at New Orleans, Louisiana, in July, 1883. It probably 
dil rs but little, however, from an adult, except in point of size, 
as ie cranial sutures have entirely disappeared. The figures of 
th Heron illustrating the text below were made from this skele- 
toi it being, I am sorry to say, the only one in my possession at 
pr silt. 1 
Upon lateral view of the skull of the Blue Heron, the 
ve ted markings of the superior mandible become more evident, 
an the line leading from the anterior point of the nostril, for- 
Wc Is, is distinctly seen. As w 7 e would naturally be led to ex- 
pe- the inferior and outer border of this mandible is a sharp 
cu ng edge, from the point where it commences by the maxillary, 
all ie way to the apex ; and the bill as a whole tapers gradually 
frc base to this latter point. 
The outline of the nostril is semi-elliptical, with abroad shelf 
of me, extending inwards from its lower margin, and becoming 
co: 'liuous with the general outside surface of the mandible, an- 
tei rly. This shelf does not meet the fellow of the opposite side, 
as very nearly does in the Yellow-Crowned Night Heron. Be¬ 
lli: , these shelves of bone are directly continuous with the 
mi illo-palatines. Above them, no nasal septum is present, and 
an perture exists to the extent shown in Fig. 2. All traces 
be een the nasal and contiguous bones have been absorbed, still 
ince writing the above paragraph. Mr. F. A. Lucas has very generously loaned me 
fro- lis own Cabinet an excellent series of skulls from specimens of A . egretta, A. can¬ 
did ma, A. ccerulea, and Nycticorax violaceus, the last mentioned being from an adult 
ind iual, and goes to support what I had already recorded throughout this memoir as 
obs r ed in the skull above referred to in the text. These specimens have been of the 
gre st assistance to me in the way of verifying the observations made upon the osteol- 
o g\ the Ardeincp upon former occasions. 
