Plate II. 



Euplectelhi imperinlift Ij. 



Fig, 4. Upper end of a specimen, 465 mm. long., in wliich the wall is still 



growing in that part. Nat. size. 

 Fig. 5. Portion of the upper end of a full-grown specimen, seen from the 



gastral side. Nat. size. 

 Fig. 6. The youngest specimen in the Sei. Coll. Mas. Body 30 mm. long. 



Nat. size. 

 Fig. 7. A young specimen, 72 mm, long. Nat. size. 

 Fig. 8, Portion of the sieve-plate and cuflt', from a full-grown specimen. 



Reduced to -/^ nat. size. 

 Fig. 9, Skeletal tube of a moderately large specimen, after washing away 



all the loose tissues. Nat. size. 

 Fig. 10. Floricome at an early stage of developing terminals, 440 x , 

 Fig. 11. A more advanced stage of same (sigmatocome stage). 440 x. 

 Fig. 12. A still more advanced stage of same. 440 x . 

 Fig. 13. Graphiocome in an early stage of developing terminals (rhaphides). 



440 X. 

 Fig. 14r<-f/. Different stages in the development of floricome-terminals, 



1000 X . 

 Fig. 15. Oxyhexaster. 440 x . 



Fig. 16. Lower end of a basal anchoring spicule. 100 x . 

 Fig, 17. Oscularia in situ. To the right, the edge of the oscular membrane. 



100 X 



