26 ZOOPHYTES. 



four weeks, other four renovated heads flourished from the mutilated ex- 

 tremities of the stalks. Vegetation proving languid, the section was re- 

 peated in a few days, for the third time, and at about the same distance 

 from the summit, which becomes always higher from prolongation of the 

 stem by the regenerating heads. The reproduction of four more which 

 now followed, was accompanied by a fifth very minute, from some stem 

 previously unobserved, all unfolding successively. Conical projections en- 

 sued ten weeks after still another section, but the regenerating principle 

 of farther living organization was exhausted. 



By the preceding experiment the prolific elements were found in the 

 stem descending still lower and lower, and their evolution, though under 

 great irregularities, was undoubtedly promoted. Low conical projec- 

 tions rise from sections when placed in an inverted position, as if prognos- 

 ticating generation, opposite to the natural direction, from the under ex- 

 tremity, now uppermost, but evolution does not follow. 



Ej^dsion. — If deep and unsightly wounds fail to injure the germi- 

 nating principle, we say it may be so subtile as to elude the edge of the 

 instrument, or so remote as to be unattainable. 



Excisions of the stalk are generally more pernicious than other 

 lacerations to the reproduction. After them a new head has sometimes 

 issued from the summit, if vacant. Sometimes, though very seldom, it 

 issues through the artificial orifice, while all the higher portion has de- 

 cayed. 



It rather appears that the excision being low, the absent head is re- 

 placed in natural course from the summit ; where high, it may issue through 

 the aperture. 



Five days after an excision three lines below the summit, a small glo- 

 bular projection issued through the wound, which in two days longer I 

 discovered, with some surprise, to be a regenerated head bursting its inte- 

 gument, and it attained sufiicient dimensions. The original head had 

 fallen previous to the excision. In another experiment, a new head issuing 

 from an excision made also about three lines from the summit, rent the 

 stalk by its enlargement. This head fell seven or eight days after pro- 

 trusion, leaving a shoot half an inch long. In 13 days another flourished 



