focated with house-hold gas. It should be killed
immediately before use, as otherwise the gastric juice attacks the
wall of the stomach, and the dissection is, in consequence, rendered
extremely disagreeable. A very young rabbit is unsatisfactory as
regards the genitalia, but otherwise there is no objection to a little
one, and it has this advantage-- that it may be immersed more
conveniently under water, in a large pie dish, for purposes of fine
dissection. The external features of the animal should be examined:
eyelids, whiskers and teeth, toes, anus, perineal space on either side
of the same, urogenital opening, and position of the ribs, vertebral
column, and limb girdles beneath the skin should be made out. Then
the animal should be pinned out through the legs, the ventral surface
uppermost, the skin opened up along the middle line from pelvic girdle
to symphyses of jaw; separated from the body wall below by means
of the handle of a scalpel, and turned back; and then the abdominal
wall should be cut into and two flaps pinned back to expose its
contents. Note the xiphisternum. The caecum and colon will be
recognised (Section 16); the stomach, the right and left central, and
left lateral lobes of the liver will probably be apparent; and the urinary
bladder (especially if distended) in the middle line behind. Without any
further dissection, but simply by turning the parts over, all the
structures of the abdomen in Figure 1, Sheet 1, will be identified.
Seek especially for and note particularly, the gall bladder, bile duct,
and portal vein, pancreatic duct, sacculus rotundus, vermiform
appendix, ureters (by pulling urinary bladder forward), genital ducts
(looping over ureters), spleen, kidneys, and adrenals. The vena cava
inferior is seen dorsally. The genital duct guides the student to the
genital gland; if the subject is a male, the testes may be exposed by
dissection, or by pulling the vas deferens gently the scrotal sac will be
turned inside out, and the testes brought into view. The ovary lies
exposed without dissection posterior to the kidney. Examine all this
carefully, and make small sketches of points of interest-- the duodenal
loop and the pyloric end of the stomach, for instance; the meeting of
colon, caecum, and sacculus rotundus again; or the urinary bladder
and adjacent parts. Note the dorsal aorta and vena cava and their
connexions behind. (Compare figure of circulation.) Cut through pelvic
girdle, and rem