342 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 11 



PLATE 6 



Figs. 1-17. Selenkothuria lubrica (Selenka). Variation of rods in 

 different individuals. Figs. 8-12, from the type specimens. 



Figs. 18-21. Selenkothuria portovallartensis (Caso). Plates and rods 

 from specimens from the Galapagos. 



(Magnification: Each division is l/lOO mm) 



I 



