70 



CORALLINES. 



collected a great di- 

 versity of these mi- 

 nute beings from that 

 part of the southern 

 coast. It grows from 

 two to four inches 

 high. The shoots are 

 slender, and always 

 erect ; the polyp cells 

 are exactly opposite. 

 Each of them is pro- 

 vided with a lid, 

 whence the name of 

 this coralline is de- 

 rived. The outer angle 

 of the aperture of the 

 cell is produced into 

 an acute point, and 

 there is a sharp tooth 

 on each side. 



We now proceed to a form unlike any already 

 noticed, which is found on shells and stones in deep 

 water, on our southern coasts, in the north of 

 England, and also in Scotland. The tubes are 

 simple, about as thick as a common sized pin, 

 but some are almost, or quite as large as those 

 in the engraving. They are sometimes divided at 

 the base, where they are twisted and flexuous, some- 

 times wrinkled at distinct intervals, horn-coloured, 

 and from six to twelve inches in height. Ellis 



DYNAMENA OPERCULATA. 



