Plate 85. 

 1-5. Pilematechinus Rathbuni A. Ag. ; Station 3374. 



1. Actinostome and adjacent surrounding plates of a specimen 85 mm. in length. 



2. Actinal system of same, seen from the interior of the test. 



3. Abactinal system and surrounding plates of a specimen 95 mm. in length. 



4. Abactinal system of same, seen from the interior. 



5. One of the abactinal plates showing the splitting of a primary interambulacral platf. 



and the resorption of the primary and miliary tubercles ; this is also shown in figs. 

 1 and 3. 



