PREPARATION OF HOLLOW VISCERA. 133 



the cat, the diaphragm must be cut through ; after division of the 

 tube, a circlet of the diaphragm may be left attached thereto. 



330. Cleansing. The organ should be manipulated in water 

 so as to expel the contents and dislodge the mucus from the ental 

 surface. When possible, as with the caecum and with the stomachs 

 of some of the lower vertebrates, the organ should be everted. In 

 any case the ental surface should be thoroughly cleansed with a 

 stream of water from a faucet or syringe. 



If desired, the capacity of the viscus may be measured as di- 

 rected in 334. 



Normal salt solution should then be thrown into the organ, and 

 it should be allowed to soak in the same for a few hours, or until 

 the blood is removed. If any part projects above the surface, it 

 should be covered with a layer of absorbent cotton. 



331. Trimming. After sufficient soaking, expel the n. s. s., 

 and place the organ upon a clean tray or dish. Provide two com- 

 pressors or some linen thread, blowpipe, coarse forceps and coarse 

 scissors curved flatwise. 



Close the free end of the oesophagus with a compressor or liga- 

 ture. Into the duodenum introduce the blowpipe, inflate the organ 

 to a moderate degree, and close the orifice with a compressor or liga- 

 ture. If the latter is employed, the orifice may be controlled by 

 the fingers of the operator or of an assistant while the thread is 

 applied. 



In trimming, the fat and vessels and connective tissue are to be 

 grasped with the forceps, and cut off close to the viscus. The con- 

 vexity of the scissors must be kept toward the organ, and care 

 taken not to wound it with the point of the forceps. 



The subsequent steps in the operation vary according to the 

 agent air or alcohol to be used for the permanent inflation. 



332. Distention with Alcohol. This is better adapted to the 

 lungs, and to delicate specimens which might not withstand the 

 pressure and manipulation involved when air is employed. 



Place the organ in 55-75 per cent, alcohol, in a dish, or better in 

 the jar in which it is to be preserved. Cut off the ligatured smaller 

 end, and secure in the orifice the canula of a syringe, or a canula 

 connected by a rubber tube with the canula of a syringe ; place a 

 ligature at the orifice ; then distend the organ with the same per 

 cent, of alcohol. If a bulb syringe is used, or if the injecting syr- 

 inge is provided with a cock, it is only necessary to tighten the lig- 



