ANIMAL PARASITES 63 



Of special significance is the fact that the endoplasm is much more 

 granular and contains ingested bacteria, spores, and cellular 

 debris. 



Demonstrations. — Study the demonstration specimens of the 

 trophozoites and cysts of the two species described above. 

 Contrast with the trophozoites those of the common intestinal 

 Endolimax nana. In this species the nuclear membrane is very 

 delicate and the chromatin material is concentrated very largely 

 in a central mass. The organism is small, the diameter averag- 

 ing that of a red corpuscle. 



References 



Boeck, W. C, and C. W. Stiles, 1923. Studies on the various intestinal 



parasites (especially amoeba}) of man. Hyg. Lab., Washington, Bull. 



133, xxvi + 202 pp. 

 Craig, C. F., 1926. "A manual of the parasitic protozoa of man," viii + 



569 pp. J. B. Lippincott Company, Philadelphia. 

 Dobell, C, 1918. Are Entamoeba histolytica and Entamoeba ranarum the 



same species? Parasitology (London), 10: 294-310. 

 Hegner, R. W., and W. H. Taliaferro, 1925. "Human Protozoology," 



xix + 597 pp. The Macmillan Company, New York. 

 Kessel, J. F., 1924. The distinguishing characteristics of the parasitic 



amoebae of culture rats and mice. Univ. Calif. Piib. Zoology, 20 (23): 



489-544. 

 Kofoid, C. A., 1923. Amceba and man. Univ. Calif. Chron., 25: 149-310. 

 Kofoid, C. A., S. I. Kornhauser, and Olive Swezy, 1919. Criterions for 



distinguishing the endamcebae of amebiasis from other organisms. 



Arch. Internal Med., 24: 35-50. 



