Wound Reparation—A ctinian Tentacles 205 
small fragment from its distal tip. Within two minutes the distal 
cut end had closed in, and a distinct nipple had formed in sub- 
stantially the same manner as when a small fragment is removed 
from the tip of an attached tentacle. The appearance of the 
piece one hour later is shown in Fig. 66. The conspicuous nipple 
is still present. [he proximal end is broadly open and deeply 
folded. 
The appearance of the proximal portion of the severed tentacle 
at this same time—about one hour and twenty minutes after the 
original operation—is shown in Fig. 6a. The tentacle was not 
artificially inflated this time, but was drawn just as it was found 
without disturbance of any kind. It has the same general form 
as that shown in Fig. 5. The nipple is narrower than before. 
There is a distinct whitish zone of contraction around the base of 
the nipple. The proximal end is broadly open and its inbent 
walls are much folded and wrinkled. Twenty-four hours after 
the beginning of the experiment the two pieces, still distinctly 
alive, presented much the same conditions as those represented 
in Figs. 6a and 6b. The nipples, however, were much less con- 
spicuous and no visible pore could be detected at the distal end of 
either piece. [he proximal piece was fixed in mercuric chlorid 
and a drawing of its proximal end was afterwards made (Fig.7). 
The need of a little internal pressure to induce the expansion of 
the piece of severed tentacle led to the arrangement of a simple 
_ apparatus whereby such pressure could be applied and controlled 
in a more practicable way than by means of a pipette. A short 
piece of glass tubing was drawn out to a curved and tapering point. 
To the other end of the piece of glass tubing a small glass funnel 
was connected by means of a bit of rubber tubing. ‘The funnel 
was supported from a wooden standard and the drawn end of the 
glass tubing was allowed to dip into the water contained in a 
small glass bowl. A large tentacle of Condylactis was detached 
from the column and removed to this small vessel. By use of fine 
forceps its proximal cut end was drawn over the tip of the glass 
tube and tied onto it by means of a ligature of soft thread. ‘The 
stimulus of cutting followed by the irritation due to picking up 
with forceps and _ to tying the ligature all combined to induce con- 
