TECHNIQUES 357 



Different species of Stentor can be grafted almost as readily as 

 individuals of the same kind by the same methods ; and in most 

 cases enduring unions are produced. 



7. Minceration 



The striped ectoplasm of stentors can be separated into 50 or 

 more disarranged patches by slicing through the surface with the 

 tip of a needle. After repeated cutting, areas will be circumscribed 

 and ''float" free on the endoplasm. Further transections of these 

 patches not only cut them in two but drag them into random 

 positions. Maximum randomness is produced if, before mincing, 

 quarter sectors of the stentor are traded — by transverse and 

 longitudinal cuts, first rotating the anterior half 180° on the 

 posterior and then the left on the right half. The latter operation, 

 or beginning minceration, will render the animal incapable of 

 directional swimming and the operation can be continued under 

 optimal conditions in a drop of medium, without further recourse 

 to methyl cellulose. 



8. Enucleation and renucleation 



If stentors are to be enucleated, abundant animals are first 

 isolated into a caster dish and left to stand for one day. The 

 stentors will then have used up much of the available food material 

 and will be largely free of food vacuoles which might be mistaken 

 for nuclear nodes. A pellucid stentor is transferred to a drop of 

 methyl cellulose on the slide with black silk. If the position of the 

 embryological lamp is adjusted so that it overthrows the specimen 

 a bit, the nodes of the macronucleus will appear as opaque white, 

 or sometimes glowing bluish bodies against the dark background 

 (see Fig. 79 a). A slice with the glass needle from the upper right 



put in place, either homopolar or heteropolar. Posterior 



remnant pushed into slit to fuse, then each remainder pulled as 



indicated to orient graft as fusion extends to it. Then cell 



remnants excised, c: Graft in placfe; in this case its anlage will 



be caused to resorb by the non-differentiating host. 



C. Head-to-head telobiotic. a: Heads of two stentors cut but 



left attached to cell bodies, b: Underparts of heads, with 



exposed endoplasms, thrust together, then excised as fusion 



spreads to the main bodies, c: Resulting telobiotic. 



