176 RAMBLES OF A NATURALIST. 



of those dreams in which the imagination often 

 indulges, we appeared to be soaring like a bird, and 

 to contemplate from some aerial height the thousand 

 varied features of hill and dale. 



Strangely formed beings were harbouring within 

 these submarine retreats, and imparted to them a 

 most characteristic physiognomy. Here and there 

 a solitary fish darted forth like a lonely sparrow 

 issuing from its covert: next, a crowded shoal 

 came forth like a flock of pigeons or swallows, 

 and winding their way along the large stones, 

 would search the tufts of waving Algae, until the 

 sight of our boat passing above their heads would 

 put the entire band to flight with every de- 

 monstration of fear. The Gorgonidse*, Caryophyl- 

 Iida3f, and a hundred different kinds of Polyzoaries 



* The Gorgonia is a genus of polypes, belonging to the order 

 of the Alcyonidse. Their polyparies, which are horny, widely 

 ramified, and often expanded like a broad fan, are very common in 

 Natural History museums. 



f The Caryophyllia belongs to the order of the ^oantho'id Polypes, 

 so called from their resemblance to certain flowers. We may 

 consider, as the type of this order, the common Actinias, which are 

 very abundant on every sea-shore, but here the individuals are 

 isolated. In a large number of the Zoanthoid Polypes, however, and 

 more especially in the Caryophyllia, the individuals are aggregated, 

 and in general their integuments and the reflected folds of the 

 membrane lining the visceral cavity, are incrusted with calcareous 

 salts, so as to form solid polyparies. (On the Polypes, we may 

 refer to the different works of Milne Edwards, and especially to 

 that which he is now publishing in conjunction with M. Haime.) 



These Zoanthoid Polypes are the principal agents in the formation 

 of those Coral islands and Madrepore reefs, which render the navi- 

 gation of the Indian Seas so dangerous. In these latitudes every iso- 

 lated rock, if it be only covered with from thirty to forty feet of water, 

 becomes the seat of a colony of these Polypes, which multiply with 



