PLUMULARIID^E. 279 



of Man (Forbes) : Dublin (Ellis) : north of Ireland (W. 

 Thompson) . 



Family IX. Plumulariidae. 



HYDROTHEC.E sessile and unilateral; ZOOPHYTE furnished 

 with nematophores (minute calycles, containing an 

 extensile offshoot from the ccenosarc, and frequently 

 bearing thread-cells}; POLYPITES with a single wreath 

 of filiform tentacles round a conical proboscis ; gono- 

 zooids always fixed. 



ANTENNULARIA, Lamarck. 



Der. From Antennula, dimin. of antenna, the feeler of an iiisect. 

 NEMERTESIA, Lamouroux. 



GENERIC CHARACTER. Zoophyte plant-like ; stems simple 

 or branching, jointed, clothed with verticillate branchlets, 

 and rooted by a mass of fibres ; hydrothecce cup-shaped ; 

 nematophores bithalamic, distributed along the stem ; go- 

 nothecce axillary, unilateral. 



THE curious ^organs which Mr. Busk has named nema- 

 tophores make their appearance in the family of the 

 Plumulariidae, and are not met with beyond it. They 

 are present in great numbers on the members of this 

 genus ; but, as a full account of them is given in the In- 

 troduction, it is unnecessary to allude to them further in 

 this place. 



