Animal Tissues for Examination. 57 



solution of chromic acid to remove particles of food, &c. ; 

 this must be done gently, and it must not be rubbed. 

 Open the intestines with scissors, and wash in dilute 

 chromic acid ; cut into short lengths. Cut out care- 

 fully the ilio-coecal valve with a portion of intestine on 

 either side. Eemove the kidneys, and open one longi- 

 tudinally, the other transversely, in two or three places. 

 Take out the spleen and pancreas and cut them in 

 small pieces. Take out some of the mesenteric glands ; 

 remove carefully the uterus and ovaries if a female. 

 Open the scrotum and remove the testes, in many cases 

 these can be got out more easily by pushing them up 

 into the abdomen. Dissect out the penis and remove 

 it. Then cut round the skin of the neck and disarticu- 

 late the skull, taking care to leave the remaining por- 

 tions of the trachea and oesophagus. Disarticulate the 

 lower jaw and remove the tongue with the trachea and 

 oesophagus ; cut off these at the base of the tongue, 

 then divide that organ longitudinally, leaving one side 

 whole, make transverse cuts in the other. If large it 

 will be necessary to make some longitudinal incisions in 

 the first for hardening with chromic acid ; but this 

 should be done so as not to interfere with making longi- 

 tudinal sections of the whole of one side. Take out the 

 submaxillary glands. The eyes and brain will then 

 only remain, and great care must be exercised in taking 

 them out. 



The best plan is to remove the brain first ; for this 

 purpose take off the covering of the nasal organ with a 

 pair of bone forceps, and snip off pieces of bone from 

 the upper part of the skull, taking care not to touch the 



