66 BJuUE HURON.
Í!|ch ami a. halt' with this, same colour of a deeper tint, the extreme tip
white; ,
When fully §edged, the bare parts, at the base of the bill, and the
basal half of the upper mandible, are light greenish-liluo, the roat black;
the lower mandible yellow, with a. patch of black, an inch and a quarter
in length on each side at th,e end. Legs, tarsi, and toes-greenish-blue,
the sides yellowish; elaws dusky. The feathers of the head are
slightly elongated; those of the back are also elongatedy but much
broader and shorter than in the adult. The feathers on the upper
part, of the head are of a faint bluish-grey. ;.: and the alular feathers
and eight outer primaries are tinged with the same colour. At
this period, the length to the; end of the tail is 22 inches, to. end of
claws, 28&; bill along the ridge 3}; wing from flexure 11; tail 4/ j ,
In November, when the moult is advanced. The bill is black,
dull blue at the base.. The feet are, nearly black, as are the claws.
The occipital feathers are now two inches and a half in length, and
some of the dorsal feathers extend as far as the tips of the «sings ; those
of the lower part of the neck hare also a length of about three inches.
The general colour of the plumage is white; the upper part of the
head, the hind neck, back, anterior edge, of ¡the.wing, and outer primaries
at the. end, of a faint bluish-grey tint; some of the elongated
feathers of the- back darker.
Length to end of tail 22 ineh.es ; to end of claws. 29^; bill 3 ;
wing from flexure 11^.
A year old. ..Bill nearly as, in the adult:; feet bluish-black, the
plumage is white, with the. upper parts pale greyish-blue as in November,
but the whole interspersed with numerous feathers of a deep
greyish-blue, similar to that of the adult; the primaries, and tail being
still white.
Length to end of tail 23j ; extent of wings¡ 32¿ ; bill 3£. Weight
9 OZ. ' .. ... , :..
At. the age of a year the..bird propagates, so that individuals in
the white, mottled, or blue plumage, may be seen bleeding together.
When only a few weeks old, the scrruture of the claw of the middle.
toe is scarcely perceptible,, exhibiting;! merely faint indications, of
points upon a, very slight margin. This margin enlarges,, and when
the bird is completely fledged the. serratur.es are perfectly formed.
BLUE HERON. 67
In : |lis b!r,j, ,a& in- most other Herons, the crura of the lower
mandible,are thin, flexible, pud elastic,, the angle filled by an elastic
membrane covered by the skin. The tongue is 1 inch long, sagittate
at the basé, tapering ïto a point, 'l'lie roof of the mouth has a median
prominent ridge, and two lateral,lines; the palate is convex ; the posterior
aperture of the riares 10 lines in length. Tie pharynx may be
dilated to I j inch ; the oesophagus, which is 12 inches .long, is when
dilated 10 lines in diameter .at -its: upper part, and gradually contracts
to 7. lines;; at the curvature of the neck it lies directly behind, having
passed down on the left side, along with the, trachea« Its walls are
•extremely thin, contrasting in this respect with the oesophagus of the
Great Northern Diver« and other swimming piseiwrous birds. The
proventricuhls is 1 inchi long, its1 glandules cylindrical, and extremely
slender. The stomach seems as if it merely formed a basal sac to
the oesophagus, its muscles being extremely thin, its tendons circular
and half an inch in diameter ; cuticular lining soft. The intestine
is long and very narrow, 5 feet 10 inches in length, 2 lines in
diameter at the upper, part, l j near the rectum, which; is 2§ inches
long, with a diameter of lines, and terminates in a nipple-like eoecum,
projecting i3> liftes beyond the -entrance of the small intestine', but
haviiig no appear:»»-« of 1he two lateral appendages usually called
caeca; In this respect, the Blue Heron agrees with others of the
Sam,s family.- The cloaca is about an inch in length and breadth.1
Thfe trachea, when extended, is? <§§ inches long. The rings 170
in number, are osseous and circular, so that the organ preserves1 its
cylindrical form M|der all circumstaneèsv They,are, like those of all
Hérons, of equal breadth oft both sides, not broad on one side
and narrow on the other, as has been represented. The contractor
muscles are very slender, as are the sterno-trâeheal ; the former send
down a slip on each side to the first bronchial ring. Thfe diameter
of the trachea is 2 lines at the upper part, 1.J at the lower. The
bronchi are short, wide, Conical, of about 13 half rings.
The right lobe of the l i v e r i s h inches long, the left lobe ; the
heart l i in length, 8 lines broad, of an oblong conical form. The stomach
contained remains of inseets and crùstaceôus animals, together
with a few seeds.
' e I