Plate II. 



EuplecteUa imperiaJis I,t. 



Fio;. 4. Upper end of a specimeD, 405 mm. long., in wliieli tlie 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. G. The youngest specimen in the 8ci. Coll. Mns. Body 30 mm. long. 



Nat. size. 

 Fig. 7. A young s]->ecimen, 72 mm. long. Nat. size. 

 Fio-. 8. Portion of the sieve-plate and cntV, from a full-grown specimen. 



Piednced to -'/s ^^^- ^^'^^e. 

 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. 14(v-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 



