324 THE BRITISH NATURE BOOK 



on a rock or stone, and are given their name of Ascidian (Greek askos, a 

 " leathern bottle ") from their similarity to a bottle with two mouths, through 

 one of which water enters, and through the other it emerges. The outer 

 coat is of a tough, leathery consistency. 



Some of them will be found at low water, but many are deep-sea inhabitants. 



One of the most curious is Botryllus violaceus, which is found on stones, 

 and looks like a flattened jelly-fish ornamented with starry patterns. As a 

 matter of fact, it is a colony of Ascidians, and not just one single individual, 

 living in a compound mass of jelly. 



The commonest is Ascidia mentula, often found in the debris from a trawler's 

 nets ; but there are some twenty species in British waters. The Currant 

 Squirter (Styela grossitlaria) is, when retracted, like a red currant, and is often 

 found on old shells. 



Sea Anemones. There are more than seventy British species of these 

 animated " flowers " of the sea. Their bodies consist of a double bag, forming 

 a kind of water jacket ; the tentacles, which spread out like the petals of a 

 flower, are tubes connected with this water jacket, and are expanded by 

 forcing the water into them. The lower part of the body is the " foot " 

 a powerful sucker by which the animal clings to its base of rock or stone ; 

 but the anemone can also crawl slowly, and on occasion will float upside down 

 on the surface of the water. 



These animals multiply sometimes by dividing into two, sometimes by 

 producing a bud, but usually by development of eggs, which they cast out 

 from their mouths in batches. Their food consists of shrimps, crabs, sand- 

 hoppers, and other small creatures, which they paralyze with poison lassoes, 

 similar to the jelly-fishes' darts, and hold down with their tentacles to digest 

 at leisure. 



The Smooth Anemone, or BEADLET (Actinia equina), is the commonest 

 of all. Its colour varies very greatly brown, olive-green, or dark crimson. 

 When the tentacles are expanded, a ring of bead-like objects is revealed of a 

 bright blue colour, from which its name is derived ; probably these are eye- 

 spots. 



The Daisy Anemone (Cereus pedunculatus) is greyish yellow in colour, 

 with fine red lines radiating from the mouth and four hundred odd tentacles, 

 and can alter its height and shape very greatly. Its tentacles are marked 

 with grey and white specks and rings. 



The Rose Anemone (Sagartia rosea) has rosy tentacles and an olive disc 

 on a brown-coloured base. It must be found at low-water mark amongst 

 the rocks when the spring tides ebb. It belongs to the rock pools at low-tide 

 limit. 



The Snowy Anemone (S. nivea) is a pale olive-brown, with white tentacles 

 and mouth. 



The Scarlet-fringed Anemone (S. miniata) has the outer row of tentacles 

 scarlet or orange-coloured, the others being brown, with darker rings. 



