Plate 15. 

 1-2. Salenia miliaris A. Ag. ; Station 3413. 



1. Seen from the actinal side, the right posterior interambulacrum occupies the ur- 



central part of the figure. 



2. The same as fig. 1, seen from the abactinal side ; the position of the test is the samv 



3-5. Dialithocidaris gemmifera A. Ag. ; Station 3382. 



3. Seen from the actinal side. 



4. Seen from the abactinal side. 



5. Seen facing the odd anterior ambulacrum. 



All figures natural size. 



