•308 LI T T L E GUILLEMOT.
inoro variety iti the structure of the digestive organs of birds, that live
principally upon animal fò^d, which has coinè under my observation ; '
and with an account of which I shall conclude the present lecture.
This bird is the Alca Alla of Linnaeus, the Little Auk. Thé termination
of the oesophagus in only known by the. ending of the; cuticular
lining, and. thé 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 halt-way to the. origin of tile ¡Efcvity,
and is there connected to a wmali gizzard, the digastric nm.<c!e of which
is strong, and a «mall 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 row*, becoming more and more numépus
towards,the lower part of the cavity, and extend to the bottom,
where it turns up. The: uxtwit of the cavity in which the. gastric
glandi arc. placed, exceed* any thing met with in the other birds that
live upon fish ; and the turn which the cavity tafes almost directly upwards,
and the gizzard being at the highest part instead of the lowest,
are peculiarities, »6 far as I am acquainted, -not met with in any other
birds of prey. This: mechanism, which will be bctKa-'understood by
examining the engraving, makes the obstacles to the food in its passage
t.. the intestines unusually great ; and the bird to digest both
fishes and sea-worms with crustáceo«« shells. It appears to be; given
for the purpose of -economizing the food in two different w a p , ^ »
• retaining it longer in the. cardiac | p | | i t h e other supplying that cavity
with a great,* quantity of gastric liquor than in other birds. This
opinion is further confirmed by th.- habits of life tftMs particular speciei'of
bird, which spends a portion of the year in the frozen regions.
Of Nava Zembla, whore the'supplies of nourishment must bikibotli
scanty and precarious." , • - - '
With respect t-o 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 AB M Lìmueus, are very similar to those
1 :of other Auks, Guillemots, Divers, and fish-eating birds in general.
The cardiac or proventricular cavity forms no curve; and the gizzard
with vfhich it-is connected, is not .»mall, nor has it merely a small por-
LITTLE GUILLEMOT. 809
tion of the internal surfaeè on each side covered with a hard cuticular
lining; for the epithelium^vers its whole surface, and is of considerable
extent. The gastric gbuids ârè not at all disposed as represented
by Sir B. 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 ,)f the Little Auk is so satisfactorily accounted for, it is
enough -hero to say, that having no foundation, it is of less than no
value, ltut 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 eolour
the water for leagues. Besides, if there were such a scarcity of food
in Nova Zembla, Why should thé birds go there? In short, the whole
statement is incorrect; and the many compilers, from Dr Çaeds to
the most recent, who have pressêd it into their service; may, in their
future editions, with propriety leave it out, and supply its place with
something equally ingenious.
This 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.