V. THE INTEGUMENT. INTEGUMENTUM COMMUNE.
The skin of the cat consists of the usual two layers, the outer epidermis and the inner fibrous corium. The skin is particularly thick and tough about the sides of the neck and face.
The skin is covered almost completely with fine soft hairs. Only the end of the nose, the pads on the soles of the feet, and the nipples are without hair. A number of long stiff sensory hairs (vibrissæ) are found on the upper lip, the cheek, and above the upper eyelid.
The pads on the soles of the feet are cushion-like projections of skin, composed largely of connective and elastic tissue and fat. There is one large pad for each foot, and in addition a small pad for each digit. The fore limb has besides a small conical pad which is situated almost exactly over the pisiform bone.
The nails are horny outgrowths of the epidermis, covering the distal phalanges.
The muscles of the skin are the cutaneus maximus and platysma; these have been described ([page 93]). The superficial facial muscles are differentiations of the skin-muscles.
APPENDIX.
PRACTICAL DIRECTIONS.
The following appendix on the dissection and study of the cat is not intended as a general treatise on methods of preservation and dissection, but attempts only to give the application of well-known methods to the dissection and study of the particular animal with which the book deals. General methods which are referred to but not described must be looked up, if unfamiliar, in the manuals of general methods.
Aids to Dissection and Study of the Cat.
—A copy of Jayne’s “Mammalian Anatomy” should be in the laboratory for reference. Only the volume on the Bones of the Cat has been issued thus far.
Wilder and Gage’s “Anatomical Technology” will be found very useful for methods of work.
The plates of Strauss-Durckheim’s “Anatomie du Chat” are exceedingly valuable for the bones and muscles, and should be in the laboratory if possible. Outline reproductions of these plates have been published by H. S. Williams (G. P. Putnam’s Sons, New York, 1875). The use of both the original plates and the reproductions is made difficult by the antiquated nomenclature used for the structures figured.
Method of Use of the Present Directions.
—Except in the case of the Bones, the order of study of the structures is usually not the same as the order in which they are described. This is of course due to practical difficulties in dissection. The present directions give the order of study, or at least the order of dissection; of course after dissection the structures can be reviewed in the logical order given in the descriptions. But in the first study and dissection, the student is to use these directions for the order of work, while using the body of the book for the descriptions. It will be necessary therefore to keep the book opened in two places,—one in the appendix, for the directions; one in the body of the book, for descriptions. In studying the muscles, for example, the student will follow the order of dissection given in the appendix, but as every muscle is dissected he will find, confirm, and study the description of that muscle given in the body of the book. Other organs are studied in a similar manner.
Before commencing the study, read that portion of the preface which explains the use of terms of direction ([page VII]).
Note that the page on which any figure is found may be determined by consulting the [list of figures] given in the [Table of Contents].