102 ANAT03UCAL TECHNOLOGY. 



its color, tlie date of killing, and the name or initials of the dis- 

 sector ; a similar tag should be attached to the jar. The cat may 

 then be suspended in the jar head downward ; all parts should be 

 immersed in the alcohol. If any parts press closely against the 

 sides, some cotton or "excelsior" should be interposed. 



If the cat can be left in the alcohol for at least a week, the parts 

 are more completely and uniformly hardened. 



§ 242. Thoracic Transection. — This is sometimes desirable 

 when only the abdominal and pelvic regions are to be examined or 

 preserved. 



The primary incision should be transverse, about 2 cm. cephalad 

 of the epigastrium. The mesosternum may be divided with the 

 nippers, and the incision then carried on either side in the 7th inter- 

 costal space. The thoracic viscera are readily separated from the 

 diaphragm, the oesophagus, aorta, and postcava may be cut 1-2 

 cm. from the diaphragm, and the dislocation of the columna verte- 

 bralis effected between the seventh and eighth thoracic vertebrse. 



If the abdominal viscera are to be preserved, strong alcohol 

 should be injected into the aorta, and into the abdomen by a slit 

 just large enough to admit the canula ; the contents of the stomach 

 and rectum should be, if possible, washed out with a stream of 

 water, aided by kneading ; alcohol should then be injected into 

 both cavities, the oesophagus tied, and the rectum plugged with 

 cotton. 



The abdominal viscera are easily displaced, and it is well to 

 let the caudal region of the body, with or without the legs, rest 

 dorsicumbent in alcohol for several days, the jar being securely 

 closed, and placed on its side in a tray. The alcohol should be re- 

 newed at the end of a week. 



§ 243. Removal of the Tail. — In some cases it may be desirable to remove the tail. 



Girdle it w^th the arthrotome near the base, and di\ade it with the nippers and bone 

 scissors. With a young animal, the bone scissors may be used without the nippers. 



With a freshly killed animal, when bleeding is undesirable, a twine ligature may be 

 tied firmly just cephalad of the point of intended removal. 



If only the muscles, vessels, and nerves are to be studied, the claw points may be 

 removed with nippers. 



