224 University of California Publications. [zoolog* 



8. davisi, as Hazen has already shown it for 8. luciae. We have 

 obtained, so far, one case which supports this view. The aboral 

 portions of the polyps used in the previous experiments were 

 inverted, so that their oral cnt surfaces came in contact with the 

 substratum. In every ease but one the pieces righted themselves 

 and regeneration of hydranths ensued. The single exception 

 remained as it was placed and developed over the cut end a 

 smooth surface which resembled a foot in appearance, though it 

 did not adhere. The piece finally died. 



Two other factors should lie noticed: size of piece and region 

 of cut. The longer pieces developed heteromorphically much 

 much more readily than the shorter ones. We have not been 

 able as yet. owing to difficulties of manipulation, to compare 

 pieces of similar length from different regions of the column to 

 determine directly the relative value of the two factors. It is 

 highly probable, however, that size is the mure important of the 

 two, since the shorter pieces produced neither foot disks nor 

 hydranths in 75 per cent of the cases, indicating a regenerative 

 capacity in general inferior to that of the longer pieces. 



