356 HISTORY OF BRITISH ZOOPHYTES. 



confess that when seen by the naked eye, it has not much 

 to recommend it. As it is pretty much the colour of the 

 Fucus that it invests, it takes a trained eye to observe it at 

 all ; and when it is seen, what is it, some would say, but a 

 brownish fleshy scarf, with some scattered spinules, giving 

 roughness to what would otherwise be a smooth glisten- 

 ing surface ? If you would look at Sir John G. Dalyell's 

 pretty figure of it, plate ix., or if I had room to tell you 

 all that he and the Rev. T. Hincks, of Exeter, have written 

 respecting it, you would own that there is more in this 

 "rough sea- mat" than at first meets the eye. "When 

 plunged in recent sea-water/' says the Baronet, "a thin 

 pale blue cloud will be speedily interposed between its dark 

 irregular surface and the spectator's eye. Let the vessel 

 sustain a shock; the cloud is instantaneously dispelled, 

 while the brownish fleshy substance remains prominent as 

 before. This illusion may be frequently repeated. The 

 semblance of a cloud arose from a multitude of hydra 

 elicited from the cells whither they had retreated, to enjoy 

 the freshness of the renovated element. Their numerous 

 pale tentacula in motion over the darker ground, caused a 

 misty shade." 



" When immersed in sea- water, first a very short white 



