Plate 56. 

 1-0. Pourtalesia Tanneri A. Ag. ; Station 3431. 



1. Seen from the actinal side, 17 ram. in length. 



2. The same as fig. 1, seen from the abactinal side. 



3. The same in profile, seen facing the right posterior interambulacrum. 



4. End view of tlie same, seen facing the odd anterior ambulacrum. 



5. Abactinal part of test of same, surrounding the abactinal system. 

 G. The same as fig. 5, seen from the interior of the test. 



