The reef itself has no passage of colour but is imitated by some shell.Purple and red and white,and green and yellow,pied and striped and clouded,the living shells wear in every combination the livery of the dead reef -if the reef be dead -so that the eye is continually baffled and the collector continually deceived.Ihave taken shells for stones and stones for shells,the one as often as the other.A prevailing character of the coral is to be dotted with small spots of red,and it is wonderful how many varieties of shell have adopted the same fashion and donned the disguise of the red spot.A shell I had found in plenty in the Marquesas I found here also unchanged in all things else,but there were the red spots.A lively little crab wore the same markings.
The case of the hermit or soldier crab was more conclusive,being the result of conscious choice.This nasty little wrecker,scavenger,and squatter has learned the value of a spotted house;so it be of the right colour he will choose the smallest shard,tuck himself in a mere corner of a broken whorl,and go about the world half naked;but I never found him in this imperfect armour unless it was marked with the red spot.
Some two hundred yards distant is the beach of the lagoon.Collect the shells from each,set them side by side,and you would suppose they came from different hemispheres;the one so pale,the other so brilliant;the one prevalently white,the other of a score of hues,and infected with the scarlet spot like a disease.This seems the more strange,since the hermit crabs pass and repass the island,and I have met them by the Residency well,which is about central,journeying either way.Without doubt many of the shells in the lagoon are dead.But why are they dead?Without doubt the living shells have a very different background set for imitation.But why are these so different?We are only on the threshold of the mysteries.
Either beach,I have said,abounds with life.On the sea-side and in certain atolls this profusion of vitality is even shocking:the rock under foot is mined with it.I have broken off -notably in Funafuti and Arorai -great lumps of ancient weathered rock that rang under my blows like iron,and the fracture has been full of pendent worms as long as my hand,as thick as a child's finger,of a slightly pinkish white,and set as close as three or even four to the square inch.Even in the lagoon,where certain shell-fish seem to sicken,others (it is notorious)prosper exceedingly and make the riches of these islands.Fish,too,abound;the lagoon is a closed fish-pond,such as might rejoice the fancy of an abbot;sharks swarm there,and chiefly round the passages,to feast upon this plenty,and you would suppose that man had only to prepare his angle.Alas!it is not so.Of these painted fish that came in hordes about the entering CASCO,some bore poisonous spines,and others were poisonous if eaten.The stranger must refrain,or take his chance of painful and dangerous sickness.The native,on his own isle,is a safe guide;transplant him to the next,and he is helpless as yourself.For it is a question both of time and place.
A fish caught in a lagoon may be deadly;the same fish caught the same day at sea,and only a few hundred yards without the passage,will be wholesome eating:in a neighbouring isle perhaps the case will be reversed;and perhaps a fortnight later you shall be able to eat of them indifferently from within and from without.
According to the natives,these bewildering vicissitudes are ruled by the movement of the heavenly bodies.The beautiful planet Venus plays a great part in all island tales and customs;and among other functions,some of them more awful,she regulates the season of good fish.With Venus in one phase,as we had her,certain fish were poisonous in the lagoon:with Venus in another,the same fish was harmless and a valued article of diet.White men explain these changes by the phases of the coral.
It adds a last touch of horror to the thought of this precarious annular gangway in the sea,that even what there is of it is not of honest rock,but organic,part alive,part putrescent;even the clean sea and the bright fish about it poisoned,the most stubborn boulder burrowed in by worms,the lightest dust venomous as an apothecary's drugs.
