<h2><SPAN name="CHAPTER_XV" id="CHAPTER_XV"></SPAN><small>CHAPTER XV</small><br/><br/> ORNITHOSAURS FROM THE UPPER SECONDARY ROCKS</h2>
<p>When staying at Swanage, in Dorsetshire, many
years ago, I had the rare good fortune to obtain
from the Purbeck Beds the jaw of a Pterodactyle,
which had much in common in plan with the <i>Cycnorhamphus
Fraasii</i> from the Lithographic Slate, which
is preserved at Stuttgart. The tooth-bearing part of
this lower jaw is 8 inches long as preserved, extending
back 3 inches beyond the symphysis portion in which
the two sides are blended together. It is different
from Professor Fraas's specimen in having the teeth
carried much further back, and in the animal being
nearly twice as large. This fragment of the jaw is
little more than 1 foot long, which is probably less
than half its original length. A vertebra nearly
5 inches long, which is more than twice the length
of the longest neck bones in the Stuttgart fossil, is
the only indication of the vertebral column. Professor
Owen described a wing finger bone from these
Purbeck Beds, which is nearly 1 foot long. He terms
it the second of the finger. It may be the third, and
on the hypothesis that the animal had the proportions
of the Solenhofen fossil just referred to, the first wing
<span class="pagenum"><SPAN name="Page_173" id="Page_173">[Pg 173]</SPAN></span>
finger bone of the English Purbeck Pterodactyle
would have exceeded 2 feet in length, and would
give a length for the wing finger of about 5 feet
3 inches. For this animal the name Doratorhynchus
was suggested, but at present I am unable to distinguish
it satisfactorily from Cycnorhamphus, which
it resembles in the forms both of the neck bones and
of the jaw. Very small Pterodactyles are also found
in the English Purbeck strata, but the remains are
few, and scattered, like these larger bones.</p>
<div class="figcenter"> <SPAN name="Fig_65" id="Fig_65"></SPAN> <span class="caption">FIG. 65. THE LONGEST KNOWN NECK VERTEBRA</span> <p class="center">From the Purbeck Beds of Swanage. (Half natural size)</p> <ANTIMG src="images/i_208a.jpg" width-obs="640" height-obs="174" alt="FIG. 65." title="FIG. 65." /></div>
<h4>ORNITHODESMUS LATIDENS</h4>
<div class="figcenter"> <SPAN name="Fig_66" id="Fig_66"></SPAN> <span class="caption">FIG. 66. CERVICAL VERTEBRA OF ORNITHODESMUS</span> <p class="center">From the Wealden Beds of the Isle of Wight</p> <ANTIMG src="images/i_208b.jpg" width-obs="640" height-obs="418" alt="FIG. 66." title="FIG. 66." /></div>
<p>The Wealden strata being shallow, fresh-water
deposits might have been expected to supply better
knowledge of Pterodactyles than has hitherto been
<span class="pagenum"><SPAN name="Page_174" id="Page_174">[Pg 174]</SPAN></span>
available. Jaws of Ornithocheirus sagittirostris have
been found in the beds at Hastings, and in other
parts of Sussex. Some fragments are as large as
anything known. The best-preserved remains have
come from the Isle of Wight, and were rewards to
the enthusiastic search of the Rev. W. Fox, of Brixton.
In the principal specimen the teeth were short and
wide, the head large and deep with large vacuities,
but the small brain case of that skull is bird-like.
The neck bones are 2½ inches long. In the upper
part of the back the bones are united together by
anchylosis, so that they form a structure in the back
like a sacrum, which does not give attachment to the
scapula, as in some Pterodactyles from the Chalk, but
the bones are simply blended, as in the frigate-bird,
allied to Pelicans and Cormorants. And then after a
few free vertebræ in the lower part of the back, succeeds
the long sacrum, formed in the usual way, of many
vertebræ. I described a sacrum of this type from the
Wealden Beds, under the name <i>Ornithodesmus</i>, referable
to another species, which in many respects was
so like the sacrum of a Bird that I could not at the
time separate it from the bird type. This genus has
a sternum with a strong deep keel, and the articulation
for the coracoid bones placed at the back of the
keel in the usual way, but with a relation to each
other seen in no genus hitherto known, for the
articular surfaces are wedge-shaped instead of being
ovate; and instead of being side by side, they obliquely
overlap, practically as in wading birds like the
Heron. I have never seen any Pterodactyle teeth so
flattened and shaped like the end of a lancet; and
from this character the form was known between
Mr. Fox and his friends as "latidens." The name<span class="pagenum"><SPAN name="Page_175" id="Page_175">[Pg 175]</SPAN></span>
Ornithodesmus is as descriptive of the sternum as of
the vertebral column. The wing bones, as far as
they are preserved, have the relatively great strength
in the fore limb which is found in many of the Pterodactyles
of the Cretaceous period, and are quite as
large as the largest from the Cambridge Greensand.
In the Sussex species named <i>P. sagittirostris</i> the
lower jaw articulation was inches wide.</p>
<div class="figcenter"> <SPAN name="Fig_67" id="Fig_67"></SPAN> <span class="caption">FIG. 67. STERNUM OF <i>ORNITHODESMUS</i></span> <p class="center">Showing the overlapping facets for the coracoid bones (shaded) behind the median keel</p>
<ANTIMG src="images/i_210a.jpg" width-obs="640" height-obs="377" alt="FIG. 67." title="FIG. 67." /></div>
<div class="figcenter"> <SPAN name="Fig_68" id="Fig_68"></SPAN> <span class="caption">FIG. 68. FRONT OF THE KEEL OF THE STERNUM OF <i>ORNITHODESMUS LATIDENS</i></span> <p class="center">Showing also the articulation for the coracoid bone</p>
<ANTIMG src="images/i_210b.jpg" width-obs="640" height-obs="416" alt="FIG. 68." title="FIG. 68." /></div>
<p>A few Pterodactyles' bones have been discovered
<span class="pagenum"><SPAN name="Page_176" id="Page_176">[Pg 176]</SPAN></span>
in the Neocomian sands of England and Germany,
and other larger bones occur in the Gault of Folkestone
and the north of France; but never in such
association as to throw light on the aspect of the
skeleton.</p>
<h4>ORNITHOCHEIRUS</h4>
<p>Within my own memory Pterodactyle remains
were equally rare from the Cambridge Greensand.
The late Professor Owen in one of his public lectures
produced the first few fragments received from
Cambridge, and with a knowledge which in its
scientific method seemed to border on the power of
creation, produced again the missing parts, so that
the bones told their story, which the work of waves
and mineral changes in the rock had partly obliterated.
Subsequently good fortune gave me the
opportunity during ten years to help my University
in the acquisition and arrangement of the finest
collection of remains of these animals in Europe.
Out of an area of a few acres, during a year or two,
came the thousand bones of Ornithosaurs, mostly
associated sets of remains, each a part of a separate
skeleton, described in my published catalogues, as
well as the best of those at York and in the British
Museum and other collections in London.</p>
<p>The deposit which yields them, named Cambridge
Greensand, may or may not represent a long period
of time in its single foot of thickness; but the abundance
of fossils, obtained whenever the workmen were
adequately remunerated for preserving them, would
suggest that the Pterodactyles might have lived
like sea-birds or in colonies like the Penguins, if
it were not that the number of examples of each
species found is always small, and the many variations<span class="pagenum"><SPAN name="Page_177" id="Page_177">[Pg 177]</SPAN></span>
of structure suggested rather that the individuals
represent the life of many lands. The collections of
remains are mostly from villages in the immediate
vicinity of Cambridge, such as Chesterton, Huntingdon
Road, Coldham Common, Haslingfield, Barton,
Shillington, Ditton, Granchester, Harston, Barrington,
stretching south to Ashwell in Bedfordshire on
the one hand, as well as further north by Horningsea
into the fens. Each appears to be the associated
bones of a single individual. The remains mostly
belong to comparatively large animals. Some were
small, though none have been found so diminutive
as the smallest from the Solenhofen Slate. The
largest specimens with long jaws appear to have
had the head measuring not more than eighteen
inches in length, which is less than half the size of
the great toothless Pterodactyles from Kansas.</p>
<div class="figcenter"> <SPAN name="Fig_69" id="Fig_69"></SPAN> <span class="caption">FIG. 69. RESTORATION OF THE SKULL OF ORNITHOCHEIRUS</span> <ANTIMG src="images/i_212.jpg" width-obs="640" height-obs="221" alt="FIG. 69." title="FIG. 69." /> <p class="center">The parts left white are in the Geological Museum at Cambridge. The shaded
parts have not been found. The two holes are the eye and the nostril<br/>
(From the Cambridge Greensand)</p>
</div>
<p>The Cambridge specimens manifestly belong to at
least three genera. Something may be said of the
characters of the large animals which are included in
the genus Ornithocheirus. These fossils have many
points of structure in common with the great
American toothless forms which are of similar geological
age. The skull is remarkable for having the<span class="pagenum"><SPAN name="Page_178" id="Page_178">[Pg 178]</SPAN></span>
back of the head prolonged in a compressed median
crest, which rose above the brain case, and extended
upward and over the neck vertebræ, so as to indicate
a muscular power not otherwise shown in the group.
For about three inches behind the brain this wedge
of bone rested on the vertebræ, and probably overlapped
the first three neural arches in the neck.</p>
<p>Another feature of some interest is the expansion
of the bone which comes below the eye. In Birds
this malar or cheek bone is a slender rod, but in
these Pterodactyles it is a vertical plate, which is
blended with the bone named the quadrate bone,
which makes the articulation with the lower jaw in
all oviparous animals.</p>
<p>The beak varies greatly in length and in form,
though it is never quite so pointed as in the American
genus, for there is always a little truncation in front,
when teeth are seen projecting forward from a position
somewhat above the palate; the snout is often
massive and sometimes club-shaped. Except for these
variations of shape in the compressed snout, which is
characterised by a ridge in the middle of the palate,
and a corresponding groove in the lower jaw, and
the teeth, there is little to distinguish what is known
of the skull in its largest English Greensand fossils
from the skull remains which abound in the Chalk
of Kansas.</p>
<p>This English genus Ornithocheirus, represented by
a great number of species, had the neural arch of
the neck bones expanded transversely over the body
of the vertebra in a way that characterises many
birds with powerful necks, and is seen in a few
Pterodactyles from Solenhofen.</p>
<p>It is difficult to resist the conclusion that the neck<span class="pagenum"><SPAN name="Page_179" id="Page_179">[Pg 179]</SPAN></span>
vertebræ were not usually more than twice to three
times as long as those of the back, and it would
appear that the caudal vertebræ in the English
Cretaceous types were comparatively large, and
about twice as long as the dorsal vertebræ. Unless
there has been a singular succession of accidents in
the association of these vertebræ with the other remains,
Ornithocheirus had a tail of moderate length,
formed of a few vertebræ as long as those of the
neck, though more slender, quite unlike the tail in
either the long-tailed or short-tailed groups of Solenhofen
Pterodactyles, and longer than in the toothless
Pterodactyles of America.</p>
<div class="figcenter"> <SPAN name="Fig_70" id="Fig_70"></SPAN> <span class="caption">FIG. 70. CERVICAL VERTEBRA, ORNITHOCHEIRUS</span> <p class="center">Under side, half natural size. (Cambridge Greensand)</p> <ANTIMG src="images/i_214.jpg" width-obs="640" height-obs="370" alt="FIG. 70." title="FIG. 70." /></div>
<p>The singular articulation for the humerus at the
truncated extremity of the coracoid bone is a
character of this group, as is the articulation of the
scapulæ with the neural arches of the dorsal vertebræ,
at right angles to them (<SPAN href="#Page_115"></SPAN>), instead of running
over the ribs as in Birds and as in other Pterodactyles.</p>
<p>The smaller Pterodactyles have their jaws less compressed
from side to side. The upper arm bone, the
humerus, instead of being truncated at its lower end
as in Ornithocheirus, is divided into two or three<span class="pagenum"><SPAN name="Page_180" id="Page_180">[Pg 180]</SPAN></span>
rounded articular surfaces. That for the radius, the
bone which carries the wrist, is a distinct and oblique
rounded facet, while the ulna has a rounded and
pulley-like articulation on which the hand may rotate.
These differences are probably associated with an
absence of the remarkable mode of union of the
scapulæ with the dorsal vertebræ. But I have
hesitated to give different names to these smaller
genera because no example of scapula has come
under my notice which is not truncated at the free
end. I do not think this European type can be
the Nyctodactylus of Professor Marsh, in which
sutures appear to be persistent between the bodies
of the vertebræ and their arches, because no examples
have been found at Cambridge with the neural arches
separated, although the scapula is frequently separated
from the coracoid in large animals.</p>
<div class="figcenter"> <SPAN name="Fig_71" id="Fig_71"></SPAN> <span class="caption">FIG. 71. UPPER AND LOWER JAWS OF AN ENGLISH PTERODACTYLE FROM THE CHALK, AS PRESERVED</span> <ANTIMG src="images/i_215.jpg" width-obs="640" height-obs="301" alt="FIG. 71." title="FIG. 71." /></div>
<div class="figcenter"> <SPAN name="Fig_72" id="Fig_72"></SPAN> <span class="caption">FIG. 72. THE PALATE OF THE ENGLISH TOOTHLESS PTERODACTYLE, ORNITHOSTOMA</span> <ANTIMG src="images/i_216.jpg" width-obs="618" height-obs="480" alt="FIG. 72." title="FIG. 72." /></div>
<div class="figcenter"> <SPAN name="Fig_73" id="Fig_73"></SPAN> <span class="caption">FIG. 73. TYPES OF THE AMERICAN TOOTHLESS PTERODACTYLE, ORNITHOSTOMA</span> <p class="center">Named by Marsh, Pteranodon</p>
<ANTIMG src="images/i_217.jpg" width-obs="480" height-obs="489" alt="FIG. 73." title="FIG. 73." /></div>
<h4>ORNITHOSTOMA</h4>
<p>The most interesting of all the English Pterodactyle
remains is the small fragment of jaw figured by
Sir Richard Owen in 1859, which is a little more than
<span class="pagenum"><SPAN name="Page_181" id="Page_181">[Pg 181]</SPAN></span>
two inches long and an inch wide, distinguished by a
concave palate with smooth rounded margins to the
jaws and a rounded ridge to the beak. It is the only
satisfactory fragment of the animal which has been
figured, and indicates a genus of toothless Pterodactyles,
for which the name Ornithostoma was first used
in 1871. After some years Professor Marsh found
toothless Pterodactyles in Kansas, and indicated
several species. There are remains to the number of
six hundred specimens of these American animals in
the Yale Museum alone; but very little was known of
them till Professor Williston, of Lawrence, in Kansas,
described the specimens from the Kansas University
Museum, when it became evident that the bones of
the skeleton are mostly formed on the same plan
as those of the Cambridge Greensand genus, Ornithocheirus.
They are not quite identical. Professor
Williston adopts for them the name Ornithostoma,
in preference to Pteranodon which Marsh had
<span class="pagenum"><SPAN name="Page_182" id="Page_182">[Pg 182]</SPAN></span>
suggested. Both animals have the dagger-shaped form
of jaw, with corresponding height and breadth of the
palate. The same flattened sides to the snout, converging
upwards to a rounded ridge, the same compressed
rounded margin to the jaw, which represents
the border in which teeth are usually implanted, and
in both the palate has the same smooth character
forming a single wide concave channel. Years previously
I had the pleasure of showing to Professor
Marsh the remarkable characters of the jaw, shoulder-girdle
bones, and scapulæ in the Greensand Pterodactyles
while the American fossils were still undiscovered.
I subsequently made the restoration of the
shoulder-girdle (<SPAN href="#Page_115"></SPAN>). Professor Williston states to
<span class="pagenum"><SPAN name="Page_183" id="Page_183">[Pg 183]</SPAN></span>
me that the shoulder-girdle bones in American examples
of Ornithostoma have a close resemblance to
those of Ornithocheirus figured in 1891, as is evident
from remains now shown in the British Museum. It
appears that the Kansas bones are almost invariably
crushed flat, so that their articular ends are distorted.
The neck vertebræ are relatively stout as in Ornithocheirus.
The hip-girdle of the American Ornithostoma
can be closely paralleled in some English
specimens of Ornithocheirus, though each prepubic
bone is triangular in the American fossils as in
<i>P. rhamphastinus</i>. They are united into a transverse
bar as in Rhamphorhynchus, unknown in the English
fossils. The femur has the same shape as in Ornithocheirus;
and the long tibia terminates in a pulley.
There is no fibula. The sternum in both has a
manubrium, or thick keel mass, prolonged in front
of its articular facets for the coracoid bones, which
are well separated from each other. Four ribs
articulate with its straight sides. The animal has
four toes and the fifth is rudimentary; there are no
claws to the first and second.</p>
<div class="figcenter"> <SPAN name="Fig_74" id="Fig_74"></SPAN> <span class="caption">FIG. 74. RESTORATION OF THE SKELETON OF <i>ORNITHOSTOMA INGENS</i> (<span class="smcap">Marsh</span>)</span> <ANTIMG src="images/i_218.jpg" width-obs="800" height-obs="311" alt="FIG. 74." title="FIG. 74." />
<p class="center">From the Niobrara Cretaceous of Western Kansas. Made by Professor Williston.
The original has a spread of wing of about 19 feet 4 inches. Fragments of
larger individuals are preserved at Munich</p>
</div>
<p><span class="pagenum"><SPAN name="Page_184" id="Page_184">[Pg 184]</SPAN></span>In
the restoration which Professor Williston has
made the wing metacarpal is long, and in the shortest
specimen measures 1 foot 7 inches, and in the longest
1 foot 8 inches. This is exactly equal to the length
of the first phalange of the wing finger. The second
wing finger bone is 3 inches shorter, the third is little
more than half the length of the first, while the fourth
is only 6¾ inches long, showing a rapid shortening of
the bones, a condition which may have characterised
all the Cretaceous Pterodactyles. The short
humerus, about 1 foot long, and the fore-arm, which
is scarcely longer, are also characteristic proportions
of Ornithostoma or Pteranodon, as known from the
American specimens. Professor Williston gives no
details of the remarkable tail, beyond saying that the
tail is small and short, and that the vertebræ are flat
at the ends, without transverse processes. In the restoration
the tail is shorter than in the short-tailed
species from the Lithographic Slate, and unlike the
tail in Ornithocheirus.</p>
<p> </p>
<p>This is the succession of Pterodactyles in geological
time. Their history is like that of the human
race. In the most ancient nations man's life comes
upon us already fully organised. The Pterodactyles
begin, so far as isolated bones are concerned, in the
Rhætic strata; perhaps in the Muschelkalk or middle
division of the Trias. And from the beginning
of the Secondary time they live on with but little
diversity in important and characteristic structures,
and so far as habit goes, the great Pterodactyles
of the Upper Chalk of England cannot be said to
be more highly organised than the earlier stiff-tailed
genera of the Lias or the Oolites. There is nothing<span class="pagenum"><SPAN name="Page_185" id="Page_185">[Pg 185]</SPAN></span>
like evolution. No modification such as that which
derives the one-toed horse or the two-toed ox from
ancestors with a larger number of digits. On the
other hand, there is little, if any, evidence of degeneration.
The later Pterodactyles do not appear
to have lost much, although the tail in some of the
Solenhofen genera may be degenerate when compared
with the long tail of Dimorphodon; but the
short-tailed types are found side by side with the
long-tailed Rhamphorhynchus. The absence of teeth
may be regarded as degeneration, for they have
presumably become lost, in the same way that Birds
now existing have lost the teeth which characterised
the fossil birds—Ichthyornis of the American Greensand,
and Archæopteryx of the Upper Oolites of
Bavaria. But just as some of the earlier Pterodactyles
have no teeth at the extremity of the jaw, such
as Dorygnathus and Rhamphorhynchus, so the loss
of teeth may have extended backward till the jaws
became toothless. The specimens hitherto known
give no evidence of such a change being in progress.
But just as the division of Mammals termed Edentata
usually wants only the teeth which characterise the
front of the jaw, yet others, like the Great Ant-eater
of South America named Myrmecophaga, have the
jaws as free from teeth as the toothless Pterodactyles
or living Birds, and show that in that order the teeth
have no value in separating these animals into subordinate
groups any more than they have among the
Monotremata, where one type has teeth and the other
is toothless.<span class="pagenum"><SPAN name="Page_186" id="Page_186">[Pg 186]</SPAN></span></p>
<p>The following table gives a summary of the Geological
History and succession in the Secondary
Rocks of the principal genera of Flying Reptiles.</p>
<div class='center'>
<table border="1" cellpadding="4" cellspacing="0" summary="">
<tr><th rowspan='2'>GEOLOGICAL FORMATIONS.</th><th colspan='2'>NAMES OF THE GENERA.</th></tr>
<tr><th>British and European.</th><th>North American.</th></tr>
<tr>
<td align='left'>Upper Chalk<br/><br/>Lower Chalk<br/>Upper Greensand<br/>Gault</td>
<td align='left'><br/><br/>} Ornithocheirus<br/>} Ornithostoma</td>
<td align='left'>} Ornithostoma<br/>} (<i>Pteranodon</i>)<br/>} Nyctodactylus<br/><br/> </td>
</tr>
<tr>
<td align='left'>Lower Greensand<br/>Wealden<br/>Purbeck</td>
<td align='left'>Ornithodesmus<br/>Doratorhynchus</td>
<td align='left'></td>
</tr>
<tr>
<td align='left'>Portland<br/>Kimeridge Clay and Solenhofen Slate<br/>Coralline Oolite<br/>Oxford Clay</td>
<td align='left'>{ Pterodactylus<br/>{ Ptenodracon<br/>{ Cycnorhamphus<br/>{ Diopecephalus<br/>{ Rhamphorhynchus<br/>{ Scaphognathus</td>
<td> </td>
</tr>
<tr>
<td align='left'>Great Oolite and Stonesfield Slate<br/>Inferior Oolite</td>
<td align='left'>Rhamphocephalus</td>
<td> </td>
</tr>
<tr>
<td align='left'>Upper Lias<br/><br/>Lower Lias</td>
<td align='left'>{ Campylognathus<br/>{ Dorygnathus<br/>Dimorphodon</td>
<td align='left'> </td>
</tr>
<tr>
<td align='left'>Rhætic<br/><br/>Muschelkalk</td>
<td align='left'>bones<br/><br/>? bones</td>
<td align='left'> </td>
</tr>
</table></div>
<hr style="width: 65%;" />
<p><span class="pagenum"><SPAN name="Page_187" id="Page_187">[Pg 187]</SPAN></span></p>
<div style="break-after:column;"></div><br />