Plate XI. 



Regadrella pliœnix 0, Sohm. 



(All figures from a specimen on board the U.S. Fish-Commission 

 Steamer ' Albatross '). 



Fio'. 1. Upper end of the specimen, seen from above. With damaged sieve- 

 plate. Nat. size. 



Fig. 2. Upper })ortion of the. same in lateral view. Nat. size. 



Fig. .3. Small portion of dermal surface with a remnant of extremely deli- 

 cate dermal latticework and with small groups of unusually large 

 dermalia in association with the hydranth of commensal flydrozoa. 

 About 10 X . 



Fig. 4. Large dermalia (prostalia marginalia) from the free edge of the ob- 

 soletely developed cuff. 100 x . 



Figs. 5, G. Strong, unequal rayed oxystauractin and oxypentactin from the 

 sieve-plate border, tlie superior ray of which gives support to radial 

 beams of the sieve-plate. 5 x . 



Fig. 7. Small portion of the superior ray above-mentioned. 50 x . ' 



Fig. 8. Portion of a sieve-plate beam. 50 x . 



