126 THE OCEAN WORLD. 



side of the pinnae. They are found in deep water all around 

 our coasts. The cells, which are the abode of the polyps are not 

 always alike in their distribution. Sometimes they are ranged on 

 two sides, sometimes on one only. Sometimes they are grouped 

 like the small tubes of an organ, at other times they assume a spiral 

 form round the stem, or they form here and there horizontal rings 

 round it." 



The Campanularinse differ considerably from the above, and 

 form a second family of this order, the ends of their branches, whence 

 the polyps issue, being enlarged into^ bell-like shape, whence their 

 name. Laomcdea dichotoma is at once the most delicate and most 

 elegant of the species. It presents a brownish stem, thin as a thread 

 of silk, but strong and elastic. The polyps are numerous : upon a 

 tree eight or nine inches high there may be as many hundreds. 

 Cajnpanularia volubilis is a minute microscopical species, living 

 parasitically on corallines, seaweed, and shelled animals. The stem 

 is a fine corneous tube, which creeps and twists itself upon its support, 

 throwing out at alternate intervals a long slender stalk, twisted through- 

 out or only partially, which supports a bell-shaped cup of perfect trans- 

 parency, and prettily serrated round the brim. Dr. Johnston found 

 the antennae of a crab so profusely infested with them as to resemble 

 hairy brushes. It is furnished, according to Hassall, with a delicate 

 joint or hinge at the base of each little cup — a contrivance designed, 

 it is imagined, to enable the frail zoophyte the better to elude the 

 rude contact of the element in which it lives, by allowing it to bend to 

 a force which it cannot resist. 



The Campanularince increase by budding, the buds being found in 

 much the same manner as in the Hydra. They form at first but a 

 simple excrescence, which, in due time, takes the form of the branch 

 from which it proceeds. These buds have their origin at certain 

 distances, and form a new series of polyps. 



CALYCOPHORIDiE. 



This order consists of free oceanic forms, provided with swimming 

 bells or nectocalyces. 



In the family of Diphyda^ but two natatory vesicles are connected 

 with the stem, as in Pray a diphyes, Fig. 42. This species is widely 

 diffused in the sea which bathes the Nicean coast, but it is very 

 difficult to procure perfect specimens of it. M. Vogt found fragments 

 more than three feet long which swam on the surface, and was in its 

 state of contraction not more thun a finger's length. This species 



