CERIANTHARIA. 



75 



pedoneme or "acontium" tlin.s intersects as a rule Ijoth the ascending and the descending limb; only 

 at the base of those craspedonemes in which tlie filaments come to an cud, is there no descending 

 limb to be found. 



The craspedonemes of tlie ciliated tract region are of two kinds. 



Texttigurc 12 



Z77^ 



kd, n^ 

 Textfigure 14. 



kd . m- 



Textfigure 13. 



Textfigure 15. Textfigure 16. 



Textfigures 12 — 16. 

 Fig. 12. Section of a craspedonenie in the ciliated tract region of Cc-n'anfkmfsis americanus. Fig. 13. Section of the most 

 aboral craspedonetne in the ciliated tract region of Pachycerianthiis maua. Fig. 14. Section of the cra-spedoneme-like cnido- 

 glandular tract of Pachycen'anthus sob'tarius. Fig. 15. Section of a so-called "acontium" (mucus-thread) of Arachnanlhus o/igo- 

 podiis. Fig. 16. Section of a craspedonenie in the craspedion region of Ceriaxthcopsis anit-ncaiius. — All sections from about 



the middle of the respective processes. 



i) Craspedonemes of the normal type which occur in man}- species usually in great numbers, 

 and have a filament limb on each side. They are found for example in C. mcmbrattacctts, P. mulH- 

 plicatiis, maua, C. aiiuricaiius (Textfig. 12). Often, as in C. viciiibranacciis, P. miiltiplicatus they are 



