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EXPLANATION OF PLATES 
Prate I 
Fig. 3 represents a tentacle of Azptasia. All of the other figures represent tentacles of Condylactis. 
Fig. 1 Stump of tentacle at an early stage of the act of extension, about ten minutes after cutting. 
Natural size. 
Fig. 2 Four tentacles, two of which have suffered loss of their distal portions. The stumps of the 
injured tentacles are fully extended, the cut ends being closed by means of the nipples. On the proximal 
portion of the normal tentacle at the right of the figure, the transverse bands. which characterize the 
entire wall of the tentacle are indicated. Natural size. 
Fig.3 Avery short stump of tentacle, closed and bearing a nipple; viewed in the plane of the surface 
of the disc. Three times natural size. 
Fig.4 A tentacle as it appeared three days after a transverse slit was cut in its wall. The wound is 
at the inside of the sharp bend in the tentacle. Natural size. 
Fig. 5 Fragment from proximal region of a large tentacle, 16 minutes after excision. The distal 
end bears a nipple. Twice natural size. 
Fig.6a The same fragment as in Fig. 5, but about an hour later. Twice natural size. 
Fig. 6b Distal portion of the same tentacle as in Figs. 5 and 6a, one and a third hours after excision 
from the proximal part of the tentacle, and one hour after the clipping of a very small fragment from its 
distal tip. The distal cut end bears a nipple. Twice natural size. 
Fig. 7 The fragment represented in Figs. 5 and 6a was fixed in mercuric chlorid 24 hours after 
excision. This figure shows a view of the proximal end of the fixed fragment. ‘Twice natural size. 
Figs. 8, 9, 10 Pieces of tentacles with proximal end tied to hydrostatic tube. The pieces are dis- 
tended under the influence of slight internal pressure. The distal ends are nearly or quite closed. 
Fig. ro shows an oblique end view of the piece. All twice natural size. 
Pirate II 
All the figures are three times natural size. 
Fig. 11 Piece of Arptasza tentacle with its proximal end tied to hydrostatic tube and under slight 
internal pressure. 
Figs. 12,13, 14,15 Each figure represents an excised tentacle of Condylactis transected into two or 
three pieces. The fragments are shown in their original axial relations to one another. Inevery frag- 
ment the larger end is the proximal end. In Fig. 14, a’ represents fragment a with its distal portion in a 
state of extreme elongation. 
Fig.16 An excised tentacle of Aiptasia cut into two pieces; a is the proximal, b the distal portion. 
Fig. 17 Anexcised tentacle of Aiptasia with its cut pistal end tied to hydrostatic tube, and under 
80 mm. internal pressure. The free proximal end is open. 
