Amoebidae 69 



The anterior portion of the intestine is inhabited by a flagellate, Giardia 

 agilis [see also p. 89] ; in various parts of the intestine and rectum 

 Endamoeba ranarum may be found; the rectum is the principal habitat 

 of three genera of flagellates, Trichomonas [see p. 67], Hexamitis, and 

 Euglenamorpha, and of several green flagellates resembling members of 

 the genera Euglena and Phacus. To study any of these in the living 

 condition, the part of the digestive tract containing them should be 

 teased out in a drop of 0.7% salt solution and covered with a cover glass. 

 Any of the species mentioned may be found with low magnification, such 

 as obtained with a 16 mm. objective and a number 5 ocular. 



Nyctotherns cordijormis is a very large ciliate that is often found in 

 the rectum of tadpoles. It appears to be a scavenger and resembles 

 Paramecium in structure and in its primary life processes. Opalina 

 ranarum is also a large ciliate. It and other species of Opalina are 

 frequent inhabitants of the rectum of tadpoles. 



Class Sarcodina, Order amoebae a, Family 



AMOEBIDAE 



PROTOZOAN CULTURES* 



George R. La Rue, University of Michigan 



NATURAL POND CULTURES 



THESE cultures should be made by the methods of Hyman, Jennings, 

 and others. The plant material collected should not be restricted to 

 Ceratophyllum and Elodea, but should include any vegetable matter, 

 e.g., old lily pads and stems, cat-tails (especially if decay has com- 

 menced), decaying leaves of trees, grass and sedges, etc., from pools, 

 ponds, marshes, bogs, ditches, and rivers. Chara and clean Spirogyra 

 and the brown mat of algae from the surface of a dam or of stones are 

 of value, if not too much is taken and if to this is added hay or other 

 materials to furnish food for bacteria. Decaying Sphagnum from 

 sphagnum bogs is valuable. Mud or ooze from the bottom of ponds or 

 pools which get the drainage from pastures or barnyards is also good. 

 In collecting this vegetable material always bring some of the water 

 from the same situation. Most Protozoa are sensitive to changes in 

 water. Treated water is particularly bad for some species and should 

 never be used until it has stood for some days in an open vessel or tank. 



* The beginner would do well to read the article by Hyman {Trans. Micr. Soc. 

 44:216, 1925) to secure some ideas concerning general methods. He should also read 

 other articles, some of which are listed at the end of these directions. 



