50 GUIDE TO THE STUDY 



Using the following key, as explained by the instructor, deter- 

 mine the eggs found. Do this for each of the samples supplied 

 for laboratory work. Note carefully the relative size of the eggs 

 and draw them to scale. 



Fig. 18. — Microscopic appearance of common objects in the feces. 1, casein 

 and fat droplets; 2, muscle fibers; 3, soap crystals; 4, crystalline fatty needles; 

 5, cholesterin crystals; 6, Charcot-Leyden crystals; 7, truffle spores; 8, portions of 

 husks of cereals; 9, hairs of wheat grains; 10, spores of fungi; 11, cells from peri- 

 carp of peas; 12, parenchyma of beans; 13, endosperm of rice; 14, vegetable 

 spirals. (After Manson-Bahr.) 



Remember that an important part of this work, is the recogni- 

 tion of plant cells, starch grains, and other food debris, pollen 

 grains, spores of fungi, and the like, which are readily confused 

 with eggs of parasites. Plant hairs and spiral plant tracheids 

 should also be noted carefully as they are not infrequently mis- 

 taken for nematode worms. 



