s these bones in something
like their relative positions. A closer approximation to the state of the
case will be reached if the student will imagine the maxilla raised up
so as to overlie and hide the palatine and presphenoid, the
squamosal similarly overlying the periotic bone, and the jugal reaching
between them. Membrane bones are distinguished by capital letters.

-Cranium_

-Nasal_ (paired), Ethmoid Bone (median), -Vomer_
-Frontal_ (paired), -Lachrymal_ (paired), Orbito-sphenoid (paired),
Pre-sphenoid (median), Eye
-Parietal_ (Paired), Ali-sphenoid (paired), Basi-sphenoid (median)*,
Periotic Bone (paired)
-Bulla_ (paired)
Supra-occipital (median), Ex-occipital (paired), Basi-occipital
(median)

-Upper Jaw_

-Pre-Maxilla_ (paired)
Palatine (paired)
Pterygoid (paired)

-Lower Jaw_

-Maxilla_ (paired)
-Jugal_ (paired)
-Squamosal_ (paired)

*In this table the small bones of the ear are simply indicated by an
asterisk.

Section 94. Hidden by the bulla, and just external to the periotic bone,
are the auditory ossicles, the incus, malleus, os orbiculare,
and stapes. These will be more explicitly treated when we discuss the
ear.

Section 95. When we come to the study of the nerves, we shall
revert to the skull, and treat of its perforations. The student should not
fail, before proceeding, to copy and recopy our figures, and to make
himself quite familiar with them, and he should also obtain and handle
an actual skull. For all practical purposes the skull of a
sheep or cat will be almost as useful as that of the dog.

6. _Muscle and Nerve_

Section 96. We have, in the skeleton, a complicated apparatus of
parts hinged and movable upon one another; the agent moving these
parts is the same agent that we find in the heart walls propelling the
blood through the circulation, in the alimentary canal squeezing the
food along its course, and universally in the body where motion
occurs, except in the case of the creeping phagocytes, and the ciliary
waving of ciliated epithelium. This agent is muscle. We have, in
muscular tissue, a very wide departure from the structure of the
primordial cell; to use a common biological expression, a very great
amount of modification (= differentiation). Sheet 7 represents the
simpler kind of muscular tissue, unstriated muscle, in which the
cell character is still fairly