SEAL CAVERN. 59 



forests of a tiny zoophyte, the delicate zigzagged 

 Laomedea. 



The damp walls of solid granite were studded with 

 marine animals, but not nearly to the extent that I 

 had anticipated. The low oval cones of the common 

 limpet were adhering to the rock, with the little shelly 

 tribes of Serpulce, and small patches of orange and 

 olive-coloured sponges ; and some parts of the sides 

 and rocky floor were plastered over with what ap- 

 peared a coating of brown mortar, but which, when 

 examined, was seen to be an assemblage of tubular 

 cells, composed of grains of sand, agglutinated together 

 by an animal cement, so as to form walls of exquisite 

 mosaic work. Each cell is inhabited by a worm 

 (Sabella alveolata) of curious structure, and instincts 

 no less remarkable. 



After we had passed the pool, the bottom consisted 

 of fine sand, wet but firm, its level sensibly rising. 

 The cavern grew every moment darker and narrower, 

 and here the candles were lighted and distributed. 

 Each of us carried a piece in his fingers, which soon 

 became streaked with stiffened streams of tallow, and 

 one fragment was committed to the lantern as a re- 

 serve in case of accidents. Southey's fine description 

 of such a cavern as this occurred to the mind : 



" The entrance of the cave 

 Darken'd the boat below. 



Around them from their nests 

 The screaming sea-birds fled, 

 Wondering at that strange shape, 



Yet unalarm'd at sight of living man, 



