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MR. W. K. PARKER OK THE STRUCTURE ART) 
bar again appears in two places, and two of the lower branchial. Here the capsule is 
complete, and the horizontal canal, and the junction of the anterior with the posterior 
canal, are seen ( Ji.s.c., a.s.c.). 
The interspace between the capsule and the basal plate admits of the exit of the 
9th and 10th nerves (IX, X); the 12th is behind, and the 7th and 8th in front, of this 
section; these two last sections show how little the ectosteal plates have affected the 
chondrocranium as yet. 
This brings me back again to the description of the adult skull, with which I began 
this paper; it is seen here how perfect the metamorphosis has been before the birth 
of the embryo. 
Conclusion. 
One of the first things suggested to the mind is the large amount of detail that has 
to be gone through in working out exhaustively the skull of this little Lizard : one of 
the smallest of the Vertebrates. 
In former days, when a mere gradational study of anatomy satisfied men’s minds, 
then both the figures and the descriptions of a Lizard’s skull cost but little trouble. 
Given, a dry museum skull, an artist’s figure, and a Comparative Anatomist to describe 
it, and the thing was done in an hour. 
In those days membrane, and even cartilage, were not reckoned among the skeletal 
tissues ; and if the centres of ossification in some “ foetus” were seen and counted, then, 
indeed, a great stroke had been made in Osteology. 
In this way, both as to the skull and the skeleton generally, the skeleton of the 
Vertebrata was easily mastered. 
The Embryologists have altered all this, and now it is no easy thing to describe 
either the skull, in part, or the skeleton as a whole. 
Half-a-century ago, to those who knew nothing of development, nothing seemed 
more self-evident than that the skull of a Vertebrated animal was composed of three or 
four vertebrae, homologous with those of the spine. 
But a new generation arose, who knew not the first framers of Vertebral theories of 
the skull; and the leader of this new race showed that we must watch the growth 
of an organism if we would understand the meaning of the parts in the adult. 
An adult—any adult—organism means a creature that has undergone a series of 
metamorphoses ; this is equally true of the Monad or the Man. 
With the burden of this truth laid upon him—no easy yoke—the writer has worked 
at this and at other types; those who know most of these subjects are the best fitted 
to judge as to whether such labour has been in vain. 
Of necessity, the morphology of the Vertebrated skeleton, if its foundation be broadly 
laid in embryology, must be a branch of biological science bristling with sharp, steely, 
technical terms. 
