OPIIIODES MIRABILIS. 231 



and twisting in all directions. When extended, they are 

 often three or four times the length of the polypite, and in 

 this state appear as most delicate, hair-like filaments. 

 My attention was first drawn to the zoophyte by a number 

 of them dispersed on the creeping stolon, which were 

 twirling themselves about in the maddest fashion, as if to 

 scare away invaders. 



One of these curious organs is almost always attached 

 to the stem a little below the calycle, and when extended 

 rises far above it ; and as it twists itself about, with its 

 formidable armature ready for instant action, it has all the 

 appearance of a purveyor or protector to the polypite. 



A striking feature of the genus Ophiodes is the con- 

 striction of the body of the polypite, dividing it into 

 two well-marked regions the oral, including the proboscis 

 and the tentacular wreath and a kind of jM^m-pharynx, 

 and the aboral, traversed by the digestive cavity. 



The polypite does not extend to the bottom of its hy- 

 drotheca, but rests on a membranous diaphragm that 

 shuts off the upper third of it and forms a cup-shaped 

 chamber. This diaphragm is perforated in the centre 

 (Plate XLV. fig. 2 c); and through the orifice the body is 

 linked on to the coenosarc, which traverses the lower por- 

 tion of the calycle. 



O. MIRABILIS, Hincks. 



Aunals N. H. for November 1866, (ser. 3) xviii. 421, pi. xiv, 



Plate XLV. fig. 2. 



STEM erect, sparingly branched, rudely annulated at the 

 base, and jointed at intervals throughout; HYDROTHEC^; 

 bulging slightly immediately above the base, with the 



