88 



KNOWLEDGE. 



[April 1, 1899. 



nesa of its hide in a way that takes no denial. It might 

 be thought that the whale would find some opportunity of 

 rubbing off these troublesome intruders and excrescences, 

 but even museum specimens will show the futility of any 

 such expectation. The deeply burrowing kinds are quite 

 sheltered from any friction short of that which would 

 scarify then- host, in which case the mighty Samson 

 would pay dearly for the ruin of his tormentors. The 

 Coronula diadema has a superficial foothold. But examine 

 the base of a specimen. Its numerous radiating com- 

 partments are occupied by a sort of black putty. That 

 putty is whale-skin, which the rightful owner would have 

 to part with in rubbing off the Cirripede. Here, too, the 

 remedy would be worse than the disease, and we have 

 striking proof that recourse is not taken to this mode of 

 relief. For on the Coronula there is sometimes quietly 

 seated a stalked Cirripede of large size, which would fall 

 like a ripe fig at the least concussion, but which has 

 obtained a practical assurance that, wherever else the rubs 

 of life may be arranged by or for a whale, they are not 

 likely to be at the point occupied by a Coronula. 



Securely embedded in the skin of a Manatee, the Platy- 

 Icpas bmexlobata may for ages have been exploring the 

 rivers of West Africa, but, apart from such rare exceptions, 



it is singular that hitherto this 

 varied and extensive group of 

 Crustacea should have neglected 

 to occupy the fresh waters of 

 the world, for to the utmost 

 limits of maritime dominion 

 it spreads its colonies with a 

 supreme indifference to the 

 character of the supporting 

 basis. Deep down on the floor 

 of the ocean, high up on rocks 

 which only the spray of a spring- 

 tide can reach, on bathing 

 machines, on floating bottles or 

 logs of wood, or in masses of 

 seaweed, on the smooth iron 

 sheathing of a ship, in rocks, in 

 corals, in sponges, in narrow 

 tunnels burrowed into shells, 

 attached to the spines of sea- 

 urchins, clinging to the feathers of sea-fowl, on the backs of 

 sea-snakes, of turtles, of crabs, fringing the very jaws of 

 crawfish and other crustaceans, sometimes conspicuous, 

 sometimes concealed, sometimes solitary , sometimes crowded 

 and multitudinous, coating vast surfaces of the wave-beaten 

 shore, they assert themselves as citizens of the world, of 

 which they occupy a far more extensive tract than man 

 does. The human organism, with its incomparable 

 superiority of brain, is, on the other hand, excessively 

 hampered by a fastidious conservatism in regard to outward 

 form. As Darwin said of the goose, so may it be said of 

 man — that his organization is very inflexible. That is 

 where the Cirripede has had the advantage of us, as a little 

 reflection will suffice to prove. 



The Crown Cirripede (Coromda diadema) is, as its name 

 implies, a stately form, proper for the pageantry of life, not 

 needing to hide its light under a bushel. But supposing 

 that by the exigencies of existence it were reduced to 

 burrowing into an oyster shell, its massive walls and 

 spreading plumes would be simply a nuisance. .Esop 

 might then have used it — instead of the antlered stag in a 

 thicket— to point the moral of his fable against conceit. 

 But, untaught by /Esop, some of our Thyrostraca (door- 

 shells) or Cirripedia (ringlet-feet) have learned to cast oif 

 everything that their alternative names suggest — shells 



Tuhicinella trachealis Sliaw, 



in skin of Right Whale. 



(Two-thirds nat. size.) 



and valves, and feet and ringlets ; everything that may be 

 regarded as specially characteristic — in order to live, as if 

 it were better to live without a character than not to live 

 at all. They come down, as it were, from the castle to the 

 cottage, from the cottage to multifarious lodgings, often of 

 the humblest kind, and end in a degraded pauperism, 

 wherein, from their shape and habits, they may, without 

 libel or slander, be described as blood-sucking sausages. 

 The division to which these last belong is known as that 

 of the Khizocephala, meaning that their heads have been 

 turned into roots, the so-called roots being narrow processes 

 which penetrate the soft part of their host, such as a 

 common shore crab, and derive nourishment from it. 



For many of the genera and species, the attachment to 

 an endless variety of moving objects sufficiently explains 

 their extensive dispersion. But many of those which love 

 a settled life are also widely spread. This is due to the 

 fact that the young are born free to move, and not averse 

 to travel. 



As for Cirripede and Thyrostracan, the giddy world still 

 knows as little about such names as fifty years ago it knew 

 about the centre of Africa. Barnacle seems to be the only 

 name to conjure with. Johnson's Dictionary, a hundred 

 years ago, defined it as " a kind of shell-fish that grows 

 upon timber that lies in the sea," and secondly as " a bird, 

 like a goose, fabulously supposed to grow on trees." As 

 is well known, earlier writers thought the bernicle or 

 barnacle goose from the tree no fable. Sir Robert Moray, 

 for instance {Phil. Trans. E. S., Vol. XI., p. 925), in every 

 shell that he opened found the bird " curiously and com- 

 pletely formed, that there appeared nothing wanting as to 

 the external parts for making up a perfect sea-fowl." " The 

 little bill, like that of a goose, the eyes marked, the head, 

 neck, breast, and wings, tail and feet formed, the feathers 

 everywhere perfectly shaped and blackish coloured, and 

 the feet like those of other water-fowl, to the best of my 

 remembrance." Seeing is believing, and we easily see 

 what we believe. But in natural history it is dangerous 

 to trust to the best of one's remembrance. Also it is not 

 good to trust too much to dried specimens. " All being 

 dead and dry," Moray continues, " I did not look after the 

 inward parts of them." The pleasing hallucination con- 

 veyed in this and many similar records is embalmed for 

 the history of science in the names of two species, Lepas 

 anatifera, the duck-bearing, and Lepas anserifera, the goose- 

 bearing barnacle. Probably the fable did more to awaken 

 and keep alive a popular interest in Cirripedes than any 

 account would have done based ou the real wonders of 

 their life-history. 



Lepas anatifera Linn. 



Lepas anaUfera, with tergum 

 and scutum remored. 



Though the barnacle never turns into a bird, its free- 

 swimming larva is scarcely more like its adult form than a 

 caterpillar is like a butterfly. At first emergence from the 

 egg-membrane the baby Cirripede is simple in structure and 



