PENNATULID&. 241 



but tapering at each extremity to a fine point. The polyps, which 

 are fleshy and white, are provided with eight long retractile tentacula, 

 beautifully ciliated on their inner edge with two series of short 

 processes strengthened with crystalline spicula. The mouth in the 

 centre of the tentacula is somewhat angular, bounded by a white 

 band, a process from which seems to encircle the base of each 

 tentaculum, which thus seems to issue from an aperture. The ova 

 lie between the membranes of the pinnae ; they are globular, of a 

 yellowish colour, and by a little pressure can be made to pass through 

 the mouth. The polyps are distributed with more or less regularity 

 in such a manner that one of the extremities of the common axis is 

 always naked : this part has been compared to the tubulous part of a 

 feather. The stem, common to the colony, is a solid central axis, 

 more or less developed, which is covered with a fleshy fibrous 

 substance, susceptible of dilatation and contraction. 



The Pennatulidce comprehend, according to Dr. Johnston, three 

 genera ; namely, those with the polyps or bipinnate wings, having 



Polypidoms plumose, in .... Pennatula. 



Polypidoms virgate, or wand-shaped . . Virgularia. 



Polypi, unilateral and sessile . . . . ) T> 



Polycom, linear-elongate . . .] Pavonana ' 



In the genus Pennatula^ the polyps are disposed in transverse 

 rows upon the outer and inner edge, in a series of prolongations in 

 the form of a feather. These winged species of polypidom are 

 somewhat scythe-shaped, well-developed, and furnished with a great 

 quantity of pointed spiculae, which are constituted of bundles at the 

 base of the calyx of each polyp. The space between the two rows of 

 appendages is sometimes scaly, sometimes granulous. Of the Penna- 

 tula, at least five species are known, and all of them appear to be 

 endowed with phosphorescent properties. We may note among these 

 species Pennatula spinosa (Fig. 97), which inhabits the Mediterranean, 

 and take? its name from its colour ; Pennatula phosphorea, which 

 abound in most European seas, being found in great plenty, clinging 

 to the fishermen's lines round our own northern shores, more 

 especially when they are baited with mussels. 



P. phosphorea is of a reddish purple, the base of the smooth stalk 

 pale ; the raches roughened with close-set papillae, and furrowed 

 down the middle ; pinnae close ; polyp cilia uniserial, tubular, with 

 spinous apertures. (Sibbald). 



Bohadsch says the Pennatula swim by means of their pinnas, 

 which they use as fishes do their fins. Ellis says, " It is an animal 



