1-11. Cystacanths from a specimen g2 mm. in diameter, including the spines. 
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ib 
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PuaTE 1. 
1-12. Podophora pedifera Agass. 
Left posterior ambulacrum, actinal side, showing a group of cystacanths. 
Expanded cystacanth, 0.92 mm. 
Side view, of another specimen, 0.92 mm. 
Seen from above; specimen of 0.90 mm. 
. Less developed with only three cysts, 0.66 mm. 
Another stage with three cysts, 0.60 mm. 
Showing the mode of attachment of the cysts to the spine, 0.71 mm. 
Profile of eystacanth of 0.54 mm. 
. Same, front view. 
Side view of one of the smallest eystacanths with three cysts, 0.41 mm. 
The same, rear view: 
Pedicellaria, to show its comparative size to the eystacanths. 
All the figures equally magnified, measurements indicate the natural size 
without the spine- 
of the sacs 
