26 A NATURAL HISTORY OF THE SEAS 



may attach themselves to small animals. Though no 

 larger than the fruit from which it takes its popular name, 

 the Sea Gooseberry does considerable damage to shoals 

 of fish fry, besides killing large numbers of larval crabs 

 and lobsters. 



Certain Ctenophores inhabiting foreign waters are of 

 a weird and beautiful design. To these belongs the ribbon- 

 shaped Venus's Girdle (Cestui), which grows to several 

 feet in length. In this animal the constant movement of 

 the prismatic swimming plates causes an unbroken 

 succession of dazzling colours to play over its entire 

 length. 



Coral is a term given to a group of polyps which manu- 

 facture a skeleton of lime. Some are solitary, but the 

 majority form colonies in which the various individuals 

 are connected by a system of tubes so that the food of one 

 is shared by all, whilst the entire assemblage is embedded 

 in and supported by spicules of carbonate of lime. The 

 skeletons may form solid stony masses as in the Precious 

 and Reef-building Corals. When the spicules are scarce 

 and scattered the result is a " Flexible Coral," of which 

 home waters supply several beautiful examples. 



The commonest perhaps is the form known by the 

 gruesome name of Dead Men's Fingers (AJcyonium), often 

 seen in its contracted form attached to oyster and scallop 

 shells. In water the little Polyps slowly expand suffusing 

 the dead creamy coloured finger-shaped mass with a rosy 

 pink flush. More striking still is the lovely Sea Fan 

 (Gorgom'a), whose spreading pinkish-orange fronds are 

 dredged just beyond low- water mark. This coral has 

 a tough horny internal skeleton, which when found washed 



