ViRGULARlA. 



Z. ASTEROIDA. 



181 



" P. stirpe Jiliformi, rachi distiche pennata : pinnis lunatis remotis 

 alternis ;" and the habitat " m O. Norvegico," seems to confirm 

 the reference. 



Virgularia differs from Pennatula remarkably in this that no spi- 

 cula enter into the composition of its soft parts. The polypiferous 

 pinnules are secund, leaving- the posterior part naked, and this is 

 marked with a deep furrow extending- from one end to the other, 

 dividing the polypidom into two symmetrical halves. 



Fig. 24. 



