Plate 89. 

 1-4. Phrissocystis aculeata A. Ag. ; Station 3366. 



1. Fragment showing the abactinal system and the surrounding plates of the abactinal 



side. 



2. Fragment of a specimen, showing the odd and the left anterior ambulacra, with the 



intervening and adjoining plates, seen from the abactinal side. The fragments ol 

 figs, 1, 2, belong to a specimen fully as large as the one figured in PI. 88, fig. 2. 



3. Fragment of a smaller specimen, showing the abactinal system somewhat more enlarged 



than fig. 1. 



4. The same, seen from the interior. 



I 



