22 LABORATORY METHODS Otf 



Exercise No. 7. Make a spread of scrapings of some 

 organ and examine. 



1. Take a knife and scrape the surface of the organ 

 and place the material on a slide; cover and examine. 



2. Note all you see, and make drawings. 



Exercise No. 8. Make a normal Salt Soiution. (NaCl. 

 7 grams to 1,000 c.c. of uwter.) 



This fluid is to be used in all cases when you want 

 to dilute the scrapings. 



Exercise No. 9. Make a spread of Spirogyra. 



SPIROGYRA. 

 1, Showing mode of reproduction; 2, nucleus. 



