Family XLIV. ALCINAE. AUKS. GENUS IV. MERGULUS, Ray. SEA-DOVE. |
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Family |
COMMON SEA-DOVE.--LITTLE GUILLEMOT. [Dovekie.] |
Genus | MERGULUS ALLE, Linn. [Alle alle.] |
This interesting little bird sometimes makes its appearance on our eastern
coasts during very cold and stormy weather. It does not proceed much farther
southward than the shores of New Jersey, where it is of very rare occurrence.
Now and then some are caught in a state of exhaustion, as I have known to be the
case especially in Passamaquody Bay near Eastport in Maine, and in the vicinity
of Boston and Salem in Massachusetts.
In the course of my voyages across the Atlantic, I have often observed the
Little Guillemots in small groups, rising and flying to short distances at the
approach of the ship, or diving close to the bow and re-appearing a little way
behind. Now with expanded wings they would flutter and run as it were on the
surface of the deep; again, they would seem to be busily engaged in procuring
food, which consisted apparently of shrimps, other crustacea, and particles of
sea-weeds, all of which I have found in their stomach. I have often thought how
easy it would be to catch these tiny wanderers of the ocean with nets thrown
expertly from the bow of a boat, for they manifest very little apprehension of
danger from the proximity of one, insomuch that I have seen several killed with
the oars. Those which were caught alive and placed on the deck, would at first
rest a few minutes with their bodies flat, then rise upright and run about
briskly, or attempt to fly off, which they sometimes accomplished, when they
happened to go in a straight course the whole length of the ship so as to rise
easily over the bulwarks. On effecting their escape they would alight on the
water and immediately disappear.
During my visit to Labrador and Newfoundland I met with none of these
birds, although the codfishers assured me that they frequently breed there. I
am informed by Mr. TOWNSEND that this species is found near the mouth of the
Columbia river.
LITTLE AUK, Alca Alle, Wils. Amer. Orn., vol. ix. p. 94.
URIA ALLE, Bonap. Syn., p. 425.
LITTLE GUILLEMOT, Uria Alle, Swains. and Rich. F. Bor. Amer., vol. ii.p. 479.
LITTLE AUK or SEA-DOVE, Nutt. Man., vol. ii. p. 531.
LITTLE GUILLEMOT, Uria Alle, Aud. Orn. Biog., vol. iv. p. 304.
Male, 7 1/8, 14 1/4.
Rare and only during winter along the coast of the United State, from New
York to Maine. More abundant along the coast of Nova Scotia, and far at sea.
Breeds on the Arctic coasts.
Adult Male in summer.
Bill shorter than the head, stout, straightish, sub-pentagonal at the base,
compressed towards the end. Upper mandible with the dorsal line
convexo-declinate, the ridge convex, the sides sloping, the edges sharp and
overlapping, the tip rather obtuse. Nasal depression short and broad; nostrils
basal, oblong, with a horny operculum. Lower mandible with the angle long and
wide, the dorsal outline very short, ascending and straight, the sides convex,
toward the end ascending and flattened, the edges thin and inclinate, the tip
acute, with a sinus behind.
Body full and compact; neck short and thick; head large, ovate. Feet
short, rather stout; tibia bare for two-twelfths of an inch; tarsus very short,
compressed, covered anteriorly with oblique scutella, behind with angular
scales; hind toe wanting; anterior toes connected by reticulated webs, the inner
much shorter than the outer, which is almost as long as the middle; the scutella
numerous. Claws rather small, moderately arched, compressed, rather acute, that
of the middle toe having its inner edge considerably expanded.
Plumage dense, blended, glossy. Wings of moderate length, narrow, pointed;
primaries pointed, the first longest, the rest rapidly graduated; secondaries
rounded. Tail very short, slightly rounded, of twelve feathers.
Bill black. Iris dark hazel. Feet pale flesh-coloured; webs dusky; claws
black. Inside of mouth light yellow. The head, upper part of neck, and all the
upper surface, glossy bluish-black. A small spot on the upper eyelid, another
on the lower, several longitudinal streaks on the scapulars, and a bar along the
tips of the secondary quills, white. The lower parts white; the feathers on the
sides under the wings have the outer webs white, the inner dusky; lower
wing-coverts blackish-grey.
Length to end of tail 7 1/8 inches, to end of claws 7 7/8, to end of wings
6 7/8, to carpal joint 2 7/8; extent of wings 14 1/4; wing from flexure 4 7/8;
bill along the ridge (4 1/4)/8, along the edge of lower mandible 1; tarsus 3/4;
middle toe 1, its claw 1/4; outer toe 1, claw (1 1/2)/8; inner toe 5/8, its claw
(1 1/2)/8. Weight 8 1/2 oz.
Adult Female in winter.
In winter, the throat and the lower parts of the cheeks are white; the
sides and fore part of the neck white, irregularly barred with blackish-grey;
the upper parts of a duller black than in summer.
There is nothing very remarkable in the anatomy of this bird, beyond what
is observed in the Auks and Guillemots. The ribs extend very far back, and,
having the dorsal and sternal portions much elongated, are capable of aiding in
giving much enlargement to the body, of which the internal, or thoracic and
abdominal cells are very large. The sub-cutaneous cells are also largely
developed, as in many other diving and plunging birds.
The roof of the mouth is flat, broad, and covered with numerous series of
short horny papillae directed backwards. The tongue is large, fleshy, 10
twelfths of an inch long, emarginate at the base, flat above, horny on the back.
The heart is large, measuring 10 twelfths in length, 8 1/2 twelfths in breadth.
The right lobe of the liver is 1 3/12 inches in length, the left 1 1/12; the
gall-bladder is elliptical. The kidneys are very large.
The oesophagus, Fig. 1, [a b c], is 3 inches 10 twelfths long, its walls
very thin, its inner or mucous coat thrown into longitudinal plates; its
diameter at the middle of the neck 5 eighths, diminishing to 4 twelfths as it
enters the thorax. It then enlarges and forms the proventriculus, [c e], which
has a diameter of 8 twelfths; the glandules are cylindrical, very numerous, and
arranged in a complete belt, half an inch in breadth, in the usual manner, as
seen in Fig. 2, [b c]. The stomach, properly so called, Fig. 1, [d g], is oblong, 11 twelfths in length, 8 twelfths in breadth; its muscular coat
moderately thick, and disposed into two lateral muscles with large tendons; its
epithelium, Fig. 2, [c d e], thick, hard, with numerous longitudinal and
transverse rugae, and of a dark reddish colour. The duodenum, [f g h], curves
in the usual manner at the distance of 1 1/4 inches, ascends toward the upper
surface of the right lobe of the liver for 1 inch and 10 twelfths, then forms 4
loops, and from above the proventriculus passes directly backward. The length
of the intestine, [f g h i], is 16 1/2 inches, its diameter 2 1/4 twelfths, and
nearly uniform as far as the rectum, which is 1 1/4 inches long, at first 3
twelfths in diameter, enlarged into an ovate cloaca of great size, Fig. 3, [b]; the coeca [a, a], 4 1/2 twelfths long, cylindrical, 1/2 twelfth in diameter, obtuse.
The trachea, Fig. 1, [k, l], is very wide, flattened, its rings unossified,
its length 2 9/12 inches, its breadth 3 twelfths, nearly uniform, but at the
lower part contracted to 2 twelfths. There are 75 rings, with 5 inferior
blended rings, which are divided before and behind. The bronchi, Fig. 1, [m, m], are wide and rather elongated, with about 25 half rings. The contractor
muscles are extremely thin, the sterno-tracheal slender; there is a pair of
inferior laryngeal attached to the first bronchial rings.
The above account of the digestive organs of this bird will be seen to be
very different from that given by Sir EVERARD HOME, who has, in all probability,
mistaken the species. "There is still," says he, "one more variety in the
structure of the digestive organs of birds, that live principally upon animal
food, which has come under my observation; and with an account of which I shall
conclude the present lecture. This bird is the Alca Alle of Linnaeus, the
Little Auk. The termination of the oesophagus is only known by the ending of
the cuticular lining, and the beginning of the gastric glands; for the cardiac
cavity is one continued tube, extending considerably lower down in the cavity of
the abdomen, and gradually enlarging at the lower part: it then turns up to the
right side, about half-way to the origin of the cavity, and is there connected
to a small gizzard, the digastric muscle of which is strong, and a small portion
of the internal surface on each side has a hard cuticular covering. The gastric
glands at the upper part are placed in four distinct longitudinal rows, becoming
more and more numerous towards the lower part of the cavity, and extend to the
bottom, where it turns up. The extent of the cavity in which the gastric glands
are placed, exceeds anything met with in the other birds that live upon fish;
and the turn which the cavity takes almost directly upwards, and the gizzard
being at the highest part instead of the lowest, are peculiarities, as far as I
am acquainted, not met with in any other birds of prey. This mechanism, which
will be better understood by examining the engraving, makes the obstacles to the
food in its passage to the intestines unusually great; and enables the bird to
digest both fishes and sea-worms with crustaceous shells. It appears to be
given for the purpose of economizing the food in two different ways,--one
retaining it longer in the cardiac cavity, the other supplying that cavity with
a greater quantity of gastric liquor than in other birds. This opinion is
further confirmed by the habits of life of this particular species of bird,
which spends a portion of the year in the frozen regions of Nova Zembla, where
the supplies of nourishment must be both scanty and precarious."
With respect to this statement and the reasonings founded upon it, it will
be seen from the description and accompanying figures above, taken directly from
nature, and without the least reference to the dissections or theories of any
person, that the oesophagus and stomach of the Little Auk or Guillemot, Alca
Alle of Linnaeus, are very similar to those of other Auks, Guillemots, Divers,
and fish-eating birds in general. The cardiac or proventricular cavity forms no
curve; and the gizzard with which it is connected, is not small, nor has it
merely a small portion of the internal surface on each side covered with a hard
cuticular lining; for the epithelium covers its whole surface, and is of
considerable extent. The gastric glands are not at all disposed as represented
by Sir E. HOME, but are aggregated in the form of a compact belt half an inch
broad, Fig. 2, [b, c]. As to the ingenious reasoning by which the economy of
the Little Auk is so satisfactorily accounted for, it is enough here to say,
that having no foundation it is of less than no value. But were there such a
curvature as that in question, there could be no propriety in supposing that it
presented any great obstacle to the passage of the food, or retained it longer
than usual. Nor is the statement as to scanty and precarious supply of
nourishment correct; for the Arctic Seas, to which this bird resorts in vast
numbers, are represented by navigators as abounding in small crustacea, on which
chiefly the Little Auk feeds, and that to such an extent as to colour the water
for leagues. Besides, if there were such a scarcity of food in Nova Zembla, why
should the birds go there? In short, the whole statement is incorrect; and the
many compilers, from Dr. CARUS to the most recent, who have pressed it into
their service, may, in their future editions, with propriety leave it out, and
supply its place with something equally ingenious.
The egg of this species measures one inch and nearly five-eighths in
length, one inch and an eighth in its greatest breadth. It is remarkably large
for the size of the bird, and of a dull uniform pale greenish-blue.
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