78 GENERAL BIOLOGY 



b) Observe the action of the fringe of strong cilia (peri- 

 stome) surrounding the rim of the trumpet, and try 

 to see objects free in the water driven by these cilia 

 into the mouth. If not well seen this may be demon- 

 strated, as for Paramoecium, by adding a little 

 finely pulverized carmine to the water. 



3. Using an eyepiece of higher magnification, study 

 the extended stentor, observing: 



a) The lorica, if present; note its shape, appearance, 



and consistency. 

 h) The disc-like attachment of the /(9c^. 



c) The long tapering body, covered with minute cilia, 



d) The flaring distal end, with its encircling peristome, 

 involute at one end to surround the mouth. Com- 

 pare with the peristome and mouth of Paramoecium. 



4. AVithin the body observe in a specimen having the 

 mouth uppermost: 



a) The short esophagus ending blindly in the endosarc. 

 h) Food -balls moved about in the endosarc. 



c) An elongate, moniliform meganucleus, and a micro- 

 nucleus close beside it. The latter is usually hard to 

 see in the living specimen, but may be demonstrated 

 with iodine as in Paramoecium. 



d) A large contractile vacuole, of varying proportions. 



e) Fine nearly parallel lines extending from foot to 

 disc in the ectosarc (myonemes) . 



5. Observe the ordinary reproduction of the animal by 

 division of the single cell into two ; note the plane of the di^d- 

 sion, and the relation it bears to foot, disc, peristome and 

 meganucleus. 



The Record of the study of the stentor may well consist in : 



1. A sketch in simple outlines of a little group of 

 stentors in various positions. 



2. The details of structure of a single animal. 



