7 0 INTRODUCTION.
of the principal muscles employed in mastication, and moreover bounding the posterior nares
and subocular cell. Unfortunately this bone is generally deficient in fossil crania.
The shape of the tympanic bone, and more particularly that of its inferior articular
surface, are useful guides to classification. Much value is also to be attached to the form
and position of the prefrontal (lacrimal, of authors), and to the circumstance whether it be
anchylosed to the cranium, or separate from it; to the form and size of the posterior nasal
fissures; to the presence or absence of the vomer, and of the ossified septum narium.
The general pneumaticity of the cranium, and the ratio in which the several elements
participate in that property, furnish less distinctive characters; the development of pneumaticity
depending on many variable conditions.
In the former part of this work the views expressed on the affinities of the Dodo by
various distinguished zoologists and anatomists, are given at length; of these, Professor Owen
alone had the opportunity of studying the evidence furnished by the foot, which led him to
regard the Dodo as an extremely modified form of the Raptorial order. In the catalogue of
the fossil remains of Mammalia and Aves in the collection of the Royal College of Surgeons,
published in 1845, apparently before he had seen the dissected foot, the Dodo is placed
among the Cursorial, or Struthious birds, from some vague resemblances in the cere and
advanced nostrils, to the corresponding parts in different members of that limited group.
The merit due to Professor Reinhardt, who from the evidence afforded by the mutilated
cranium in the Gottorf Museum, assigned to the Dodo, thus bandied about, a final resting
place among the Pigeons, has been freely conceded by his fellow-labourer, Mr. Strickland;
who, however, from a minute and accurate comparison of the bones of the leg with those of
other types, had arrived at the same goal, by a different, but equally certain path. The idea
once attained served to elucidate the true relations of the cere and advanced tubular nostril,
which had hitherto been misunderstood; the disappearance of the mandibular horny sheath
was also readily explained by the facility with which it desquamates in other members of this
group. Some learned ornithologists admit, that the correct interpretation of these external
characters alone, might have led to the proper allocation of this strange and almost fabulous
creature.
From anxiety to obtain the fullest information, application was made to Mr. Duncan,
Keeper of the Ashmolean Museum, for permission, which was liberally granted, to remove
the integuments from the left side of the head of the Dodo, where they were most decayed,
and the requisite dissection was judiciously performed by the Reader of Anatomy, Dr. Acland.
During this procedure, the leading points of resemblance between the cranium and that of
the Pigeons were pointed out by Mr. Strickland, who has kindly associated the writer with
him, in the task of describing the remains of this extinct form and its aftine, the Solitaire.
My testimony, hence, is that only of an impartial observer with no hypothesis to defend,
and who claims no share in the merit due to those who have succeeded in restoring the Dodo
to its proper rank.
THE
N A T U R A L H I S T O RY
OF THE
DODO, S O L I T A I R E , & c
PART II.
C H A P T E R I.
Osteology of the Dodo.
(PLATES VIII., IX., X., XI., and XII.)
The skull of the Dodo is larger than that of any existing raptorial bud, and greater
though shorter than that of the Albatross; its ratio to that of the Goura and Treron will be
seen by a glance at Plate X.
The skull is remarkable not only for its great absolute and relative size, but also, for the
abbreviation of the cranium, whose length is to that of the upper mandible as one to two,
and for the sudden rise of the frontal region above the compressed upper mandible; the
skull hence assumes, as it were, the form of a mallet, the head of which corresponds to the
cranium, while the core, or bony termination of the mandibles, acts as a counterpoise.
The shortening of the cranium is due to the small relative size of the eyes, and the
consequent retrogression of the ethmoidal fossa;, and atrophy of the proper interorbital septum.
The elevation of the frontal region above the level of the upper mandible, is produced
by a sudden expansion of the pneumatic diploe, tilting up the extremity of the mesial
process of the premaxillary, and the body of the nasal on each side, at an angle of 45°;
while the abbreviated frontal is raised into a broadly rounded interorbital eminence.
There is a similar development of the diploe, though in a less degree, in the Goura. The
rise of the frontal region is in some Pigeons more abrupt than in the Dodo, but is owing to a
different cause; namely, the great size of the orbit, and the relative slenderness of the bill.