PENNATULA. 195 



in proportion to tlie size of the stem, which is about the 

 third of an inch in diameter. The breadth of the lobed or 

 feather part is about an inch and a half. There are several 

 polypes on each lobe, — in all, about thirty. It is rare in 

 England and in Ireland, but in the north of Scotland it is 

 frequently found on the fishermen's lines when baited with 

 mussels. In the Frith of Eortli it is common. Sir J. G. 

 Dalyell, who describes and figures it admirably, had sixty- 

 four live specimens at once in his possession. He states 

 that, ^^ike other asteroid zoophytes, it is strictly a noc- 

 turnal animal. It enlarges remarkably as evening comes 

 on. It is then that the lobes are swollen, and the hydrse 

 most amply displayed in vigour, wliile the whole variable 

 organic structure expands by intumescence.''^ 



Whether it can swim about, or remains fixed in the mud 

 or sand, is a disputed point. There is high authority in 

 proof of its natatory powers. Bohadsch says that it swims 

 freely, and that he has seen it do so, using its pinnae for 

 this purpose as fishes do their fins. . Ellis says " it is an 

 animal that swims freely about in the sea," and that this is 

 effected by means of feather-hke fins. Cuvier tells us that 

 it has the power of moving by the contractions of the globe 

 part, and the combined action of the polypes. Other na- 



