POST-MORTEM EXAMINATION OF ANIMALS. 261 



and by twisting it about after its introduction particles 

 of the tissue sufficient for examination are withdrawn 

 in the eye of the spear-head. 



FIG. 53. 



Nuttall's platinum spear for use at autopsies. 



Cultures from the blood are usually made from 

 one of the cavities of the heart, which is always punct- 

 ured at a point which has been burned in the way 

 given. 



In addition to cultures, cover-slips from the site of 

 inoculation, from each organ, and from any exudates that 

 may be present must be made. These, however, are 

 prepared after the materials for the cultures have been 

 obtained. They need not be examined immediately, 

 but may be placed aside, under cover, on bits of paper 

 upon which the name of the organ from which they were 

 prepared is written. 



When the autopsy is complete and the gross appear- 

 ances have been carefully noted, small portions of each 

 organ are to be preserved in 95 per cent, alcohol for 

 subsequent examination. Throughout the entire au- 

 topsy it must be borne in mind that all cultures, 

 cover-slips, and tissues must be carefully labelled, 

 not only with the name of the organ from which 

 they originate, but with the date, designation of the 

 animal, etc., so that an account of their condition 

 after closer study may be subsequently inserted in the 

 protocol. 



The cover-slips are now to be stained, mounted, and 



