Imatges de pÓgina
PDF
EPUB

above. But what-and how much? eyes. They were in cipher! Yes, it That was the question. We com- looked like cipher. Fancy a man lugmented adversely upon the imbecility ging with him a book of that descripof that telegraphic style. The bush tion into this nowhere, and studying it around said nothing, and would not let and making notes-in cipher at that! us look very far, either. A torn cur- It was, indeed, an extravagant mystain of red twill hung in the doorway tery. of the hut and flapped sadly in our "I had been dimly aware for some faces. The dwelling was dismantled; time of a worrying noise, and when I but we could see a white man had lived lifted my eyes I saw the woodpile was there not very long ago.

There re- gone, and the manager, aided by all the mained a rude table-a plank on two pilgrims, was shouting at me from the posts; a heap of rubbish reposed in a riverside. I slipped the book into my dark corner, and by the door I picked pocket. I assure you to leave off read. up a book. It had lost its covers, and ing was like tearing myself away from the pages had been thumbed into a the shelter of an old and solid friendstate of extremely dirty softness; but ship. the back had been lovingly stitched "I started the lame engine ahead. 'It afresh with white cotton thread, which must be this miserable trader—this inlooked clean yet. It was an extraordi- truder,' exclaimed the manager, looknary find. Its title was 'An Inquiry ing back malevolently at the place we into Some Points of Seamanship,' by a had left. 'He must be English,' I said. man Tower, Towson-some such name 'It will not save him from getting into -master in His Majesty's navy. The trouble if he is not careful,' muttered matter looked dreary reading enough, the manager, darkly. I observed with with illustrative diagrams and repul- assumed innocence that no man was sive tables of figures, and the copy was safe from trouble in this world. 60 years old. I handled this amazing “The current was more rapid now, antiquity with the greatest possible ten- the steamer seemed at her last gasp, derness, lest it should dissolve in my the stern wheel flopped languidly, and hands. Within, Towson or Towser was I caught myself listening on tiptoe for inquiring earnestly into the breaking the next beat of the float, for, in sober strain of ships' chains and tackle and truth, I expected the wretched thing to other such matters. Not a very en- give up every moment. It was like thralling book; but at the first glance watching the last flickers of a life. But you could see there a singleness of in- still we crawled. Sometimes I would tention, an honest concern for the right pick out a tree a little way ahead to way of going to work, which made measure our progress towards Kurtz these humble pages, though out so by, but I lost it invariably before we many years ago, luminous with another got abreast. To keep ine eyes so long than a professional light. The simple on one thing was too much for human old sailor with his talk of chains and patience. The manager displayed a purchases made one forget the jungle beautiful resignation. I fretted and and the pilgrims in a delicious sensa- fumed and took to arguing with myself tion of having come upon something whether or no I would talk openly with unmistakably real. Such a book being Kurtz; but before I could come to any there was wonderful enough, but still conclusion it occurred to me that my more astounding were the notes pen. speech or my silence, indeed any action ciled in the margin and plainly refer- of mine, would be a mere futility. What ring to the text. I couldn't believe my did it matter what any one knew or ignored? What did it matter who was affair lay deep under the surface, bemanager? One gets sometimes such a yond my reach and beyond my power flash of insight. The essentials of this of meddling. Blackwood's Magazine.

(To be continued.)

MIMICRY AND OTHER HABITS OF CRABS.

While standing recently in the vesti- ment cells in the skin, is the involuntary bule of the South Kensington Natural cause of most of the varying colors in History Museum, in presence of the these creatures. But I am led to bestatue of Darwin, I noticed a statement lieve that this, in itself, is a slow procon a placard to the effect that in reality ess, and would take a considerable our knowledge of the actual habits and time to develop changes, whereas all life history of animals in a state of the cuttles and many other forms of naturę is comparatively meagre. This sea life can instantly change from one is almost inevitable, since such knowl- color to another; and I can scarcely see edge can be secured only by observa- how this can be done, except by the tion, which in many cases is necessarily eye, through the nervous system acting deficient and almost impossible. Partic- on the will. ularly is this so in the case of marine Hence the question may be asked: life; and even more when the special How can the crab show these changes, phase of that life is predominantly sub- having no skin, and hence no active marine. Here observations become ex- color sacs, like the cuttles, wherewith ceedingly difficult, and it is only after to distribute this coloring matter? much patience that nature is made to To this I remark that the carapace, yield even a scanty portion of her or shell of the crab, in addition to being secret.

the bones and framework of the animal, It may be well to record some new is also its true skin; a thick, massive phases I have noted of mimicry and armor, certainly, but possessing all other activities in crabs. For, few necessary conditions of the skin. Hence though they be, they will help, never- the hairs growing on various parts of theless, to swell the mass of facts the body, especially near the head, are necessary to the final record of life in in touch with the nervous system; and the sea, which at present seems such the means for changing color, though a vast realm of mystery.

much slower, are provided somewhat The word “mimicry" I shall employ on the same lines as in the case of the here in its broadest sense. Messrs. cuttles. Bate and Wallace have used it in con- The carapace is mostly composed of nection with butterflies imitating each carbonate of lime; and the coloring of other. I shall use it of crabs simula- the shell depends on a pigment which ting their surroundings. I am not aware pervades different parts of the subthat mimicry in any of the higher in- stance. This lime and earthy matter habitants of the sea has been treated is drawn from the sea by an organized by any one before. Some who have membrane, and is at the will of the glanced at the subject seem to favor creature. the idea that light, acting on the pig. My first difficulty with this subject, after puzzling over the remarks of varied existence; for most of the fePieper, Poulton, Simroth, Cunningham, males which have not spawned in the Newbigin and others, with their nega- sands have to pass through the process tion or approval of protective colora- of exuviation. At a later date, as the tion, natural selection, mimicry and summer advances, they retire to the color in nature, has been whether the roughest grounds in the neighborhood, acts I shall describe in these creatures generally at extreme low water spring are voluntary or involuntary. In the tides; and on the sheltered side, away mimetic coloring of the butterflies given from the dash of the sea, under the by Wallace it would seem that the largest stones, they scoop out for themlatter word represents their case. But, selves homes, where they pass through in the face of the facts I shall produce,

this difficult and important change. there will appear a doubt whether this Here in a few days they sometimes idea can be applied to any of these double their size and develop from marine creatures.

puny maidens into full-grown crabs, Hypothetically, this article favors when they are followed by the males, the view that the action of crabs in whose first act is to enlarge their mimicking their surroundings is volun. dwelling, seeing they are about tary; but the question whether volun

one-third larger than the females. To tary or involuntary is for future de. the best of their ability the males here cision, when more abundant facts have protect the weaker sex from their enebeen collected.

mies in passing through this plastic and My first remarks will be on Carcinus helpless condition; and, on the partial mænas,' or the common

hardening of the carapace, continue the

final act of congress in their domestic SHORE CRAB.

retreats. It was long thought at these crea- Here, also, in the late summer, may tures, at the beginning of autumn, left be found females spawning, which were the shallow and tidal harbors of Devon not ready for this act, in the sands, and Cornwall and went into the deep during the spring. How far into the sea; but it has been discovered that

autumn spawning is continued it is they really do not go far out, but sim- difficult to decide, on account of the ply burrow under he sands, just out- tides, but young crabs, in their first side low water spring tides.? There

forms, may be found on the coasts they exist through the winter in a semi- from June to January. torpid condition; and while in this state

Up to this point I have only been desuch of the females as have spawn in scribing the shore crabs on the open them transfer their eggs from the in- coasts; but in our natural deep-water ternal shell to the underpart of the harbors, such as Plymouth and Fowey, flap or tail by a beautiful and involun- where they are sheltered from the wintary process. It would seem that be- ter storms which beat upon the shore, fore they leave this sheltered position their practice varies very much from in May the eggs are cast in the sand, that of those which live outside. and are alive in about forty-eight hours There they never take up the hybernaafter being shed.

ting habit and have a winter's rest like But this is only one side of their their congeners in the open sea, but are

1 For the names of crabs I shall follow Bell; of cuttles, Gosse; of fishes, Couch; of seaweeds, Grattann.

? If the sands are not convenient, the crabs will

be found near in the most sheltered position where stones are plentiful, just outside low water spring tides.

forever in waking hours on the alert, nippers is powerful. I have known and only use the sands or mud for them hold on to the lifting of over rest, protection and the final acts of eighty times their own weight. procreation.

But notwithstanding this strength Let us consider again their general and courage, they know well the diffhabits in the open sea. Beside being culty there is in living near the shore, scavengers of the shore, they prey upon with the sea-birds, man and an army every living organism near them; and of rats as their inveterate enemies. as they can see just as well out of Moreover, in the great light of our shalwater as in it, they will sometimes low seas, their chief trouble is in getcrawl short distances out of the sea to ting any kind of living food. Hence secure some dainty food; and on sea the whole race, with more than human beaches, when hunger presses them tenacity, cling to mimicry as the sheethard, they will even come above the anchor of life; and when many of its waves at high water and hunt after the varied forms of deception fail, they sand-hoppers there.

have no hesitation in simulating death, These anxious business habits are as will be seen as I proceed. On the very attractive to the children of the coasts of Cornwall, near Mevagissey, coasts, who often receive their first the powdered white sca-shells mixed fishing lessons in the capture of these with the broken mica-schist rocks give little sinners, with thread and pin hook. us a brown sand. These are often interIt is said that rats fish for them in the spersed with white markings from same way, using their own tails as quartz pebbles; hence the first act of lines and bait. Of this, I think, there many young crabs here in the spring can be no doubt, the great hunting. is to color their carapace brown with ground of the rats throughout the sum- white spots. mer and autumn being the coast-line On Portmelon beach, where the brown of the sea, and their quarry chiefly

sands and the white shingle mix freely these crabs. Mevagissey old pier was together, I have seen crabs up to an built without lime, and it is not un- inch and a half across the back with common to see rats, between high and these white markings prominent, wherelow water, hunting through this struc- as the same sized crabs in Mevagissey ture for these invertebrata. On one pier on the black mud assume a dark occasion I saw a rat with its hinder green, approaching an almost pitchy parts sodden with water, while the tip hue; while on the open coasts in the of its tail was quite white, as if it had summer months, between high and orjust been used as a bait.

dinary low water, the principal color is These shore crabs, although less than green, because of the preponderance of three ounces in weight and their cara- green sea-weeds there. This, however, pace seldom stretching to three inches, is modified into light and dark hues by when cornered in difficulties will face the presence of dark mud and stones or any enemy, however large. Possibly light sands and shells. In all these these fighting proclivities may have

shades the crabs imitate their environbeen intensified by the fact that from ments, even to giving the white patch the first dawn of existence they have on their carapace a greenish tinge, never had any kind of maternal or pa- especially in the pools, where it either rental assistance, having had to fight the

hides them from their enemies or gives battle of life alone. The grip of their

them better opportunities of pouncing

on living food; whereas at extreme 3 On many parts of the coast they are called by

low water, in their chosen retreats un. this name.

der the stones, where coral and worm at once, and they came up to him with
life give a red hue to their surround- extended antennæ,' and either touched
ings, the males and some females dress or smelt his nippers, and quickly passed
the whole of their exposed parts in a by on the other side. This was done
red color, and even the brown back again and again, but he stood like a
wbich is mostly hidden, has a red tinge. statue under their scrutiny. At last

Their feigning death is often seen one of the prawns seemed to come a
after a fight or a struggle for life in little nearer than the others, and the
which they have been badly worsted. final rush and nip were given, but
This often happens when, after being without effect, for the feelers were
caught in a shore seine, all their efforts quickly withdrawn, and with a flip of
to escape have failed, and they are the tail the creature was out of reach.
drawn in on the beach. Then their sim- But although unsuccessful, the crab
ulation of the end is almost perfect. was not without further resources. His
This is also seen when they are fight- next move was to look around the track
ing with the human hand and are over- a little, and soon he found some green
come. Then the assumption of death sea-weeds near. These he touched up
is their final act; sometimes it takes the lightly, and after moving them a little
form of rigidity of limbs, as if they more to the centre, he quietly got into
were dying in a fit, and at other times the middle of them, and again stood
a rag-like limpness as if life were gone. up with extended claws and open nip-

To show that these creatures have pers. Here the green crab, in these
an innate desire for this kind of trick- green garments, was fairly hidden,
éry, let me describe half an hour in Quickly but cautiously again came on
the life of one of them.

the

prawns. Soon their antenna
Some time ago I was waiting for the struck his open nippers in the weeds,
tide to come into a neighboring harbor, and again in cautious haste they moved
and with its advances I noticed that away.
quantities of young prawns were anx- Patience is said to be a virtue, and
ious to explore its mud and sea-weed, if it is so, this little crab had a good
and that in the long furrow made by share of it, for more than a score of
the last ship's keel, these active creatures these prawns touched his nippers in the
came along by the score. Many had weeds, and went their way without
not passed in before Carcinus menas coming within gripping distance of the
came to the front, out of the mud. At silent watcher.
once he showed me he had a design At last his virtuous feelings became
on the life of these prawns, for he

exhausted, and he rushed with violence
quietly crept into the keel-mark and on his wary neighbors, but without ef.
stood across their track with extended fect, for, with a swift move of their
claws and open nippers; and in his tails, they were out of danger. But the
green-gray form, covered with dirt and crab's artifice was not yet ended. After
mud, he could scarcely be seen on the

taking a little rest (for now his arms sea bottom. Here he waited to grapple

must have been as weary as those of with the first comer. But wariness the disobedient schoolboy after the barely expresses the watchful care of punishment of holding out his book) these prawns, for the crab was noted he began to search for a soft place on

[ocr errors]
[ocr errors][ocr errors]

• Professor Milne Edwards regards the inner pair of antennae, in crabs generally, as organs of smell, and the outer and longer pair as organs of bearing. As prawns have three pairs of an

tennae, we are led to believe from the actions of these creatures that the third and longer pair are

organs of feeling, and, to some extent, Answer the purpose of the human hand.

« AnteriorContinua »