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organisms has not come under consideration. rings, the bending or the extension of the tail results. Morphology and distribution might be studied Close observation of the newly-opened lobster would almost as well, if animals and plants were a soon show that all its movements are due to the peculiar kind of crystals, and possessed none of same cause--the shortening and thickening of these those functions which distinguish living beings so fleshy fibres, which are technically called muscles. remarkably. But the facts of morphology and dis Here, then, is a capital fact. The movements of tribution have to be accounted for, and the science, the lobster are due to muscular contractility. But whose aim it is to account for them, is physiology. why does a muscle contract at one time and not at
Let us return to our lobster once more. If we | another? Why does one whole group of muscles watched the creature in its native element, we contract when the lobster wishes to extend its tail, should see it climbing actively the submerged rocks, and another group, when he desired to bend it? among which it delights to live, by means of its | What is it originates, directs, and controls the strong legs; or swimming by powerful strokes of motive power ? its great tail, the appendages of whose sixth joint Experiment, the great instrument for the ascerare spread out into a broad fan-like propeller; seize tainment of truth in physical science, answers this it and it will show you that its great claws are no question for us. In the head of the lobster there mean weapons of offence; suspend a piece of carrion lies a small mass of that peculiar tissue which is among its haunts, and it will greedily devour it, known as nervous substance. Cords of similar tearing and crushing the flesh by means of its matter connects this brain of the lobster, directly or multitudinous jaws.
indirectly, with the muscles. Now, if these comSuppose that we had known nothing of the lobster municating cords are cut, the brain remaining entire, but as an inert mass, an organic crystal, if I may the power of exerting what we call voluntary motion use the phrase, and that we could suddenly see it in the parts below the section is destroyed, and on exerting all these powers, what wonderful new ideas the other hand, if, the cords remaining entire, the and new questions would arise in our minds ! The brain mass be destroyed, the same voluntary mobility great new question would be, “How does all this l is equally lost. Whence the inevitable.
is equally lost. Whence the inevitable conclusion take place ?” the chief new idea would be the idea is, that the power of originating these motions of adaptation to purpose,—the notion that the con resides in the brain, and is propagated along the stituents of animal bodies are not mere unconnected nervous cords. parts, but organs working together to an end. Let In the higher animals the phenomena which attend us consider the tail of the lobster again from this transmission have been investigated, and the this point of view. Morphology has taught us that | exertion of the peculiar energy which resides in the it is a series of segments composed of homologous nerves, has been found to be accompanied by a disparts, which undergo various modifications-beneath turbance of the electrical state of their molecules. and through which a common plan of formation is If we could exactly estimate the signification of discernible. But if I look at the same part physio- this disturbance ; if we could obtain the value of a logically, I see that it is a most beautifully con given exertion of nerve force by determining the structed organ of locomotion, by means of which quantity of electricity or of heat of which it is the the animal can swiftly propel itself either backwards equivalent; if we could ascertain upon what arrangeor forwards.
ment, or other condition of the molecules of matter, But how is this remarkable propulsive machine | the manifestation of the nervous and muscular made to perform its functions ? If I were suddenly energies depends (and doubtless science will some to kill one of these animals and to take out all the day or other ascertain these points), physiologists soft parts, I should find the shell to be perfectly would have attained their ultimate goal in this direcinert, to have no more power of moving itself than tion; they would have determined the relation of is possessed by the machinery of a mill, when dis the motive force of animals to the other forms of connected from its steam-engine or water-wheel. | force found in nature; and if the same process had But if I were to open it, and take out the viscera been successfully performed for all the operations only, leaving the white flesh, I should perceive that which are carried on, in and by, the animal frame, the lobster could bend and extend its tail as well as physiology would be perfect, and the facts of morpho. before. If I were to cut off the tail I should cease | logy and distribution would be deducible from the to find any spontaneous motion in it-but on pinch laws which physiologists had established, combined ing any portion of the flesh, I should observe that with those determining the condition of the surit underwent a very curious change-each fibre be- | rounding universe. coming shorter and thicker. By this act of contrac There is not a fragment of the organism of this tion, as it is termed, the parts which the ends of the humble animal, whose study would not lead us into fibre are attached are, of course, approximated; regions of thought as large as those which I have and according to the relations of their points of briefly opened up; but what I have done, I trust, attachment to the centres of motion of the different has not only enabled my readers to form a conception
of the scope and purport of zoology, but has given her reach; privately, to deposit her eggs safely in a an imperfect example of the manner in which, in fitting situation, to insure the perpetuation of her my opinion, that science, or indeed any physical species. Madam and all her kindred have a disscience, may be studied. The great matter is to agreeable fondness for my blood, why or wherefore make the study real and practical, by fixing the is not easy of explanation, and invariably make me attention on particular facts; but at the same time their especial victim. So surely as I am enjoying it should be rendered broad and comprehensive by myself, it matters not how many persons are present, constant reference to the generalizations of which I always observe these blood-loving amazons prefer all particular facts are illustrations. The lobster to leave the rest, and, with self-satisfied hums, make has served as a type of the whole animal kingdom, straight for me, tocrowd into my ears and up my nose, and its anatomy and physiology have illustrated for and, as though they were “ile seekers,"each one there us some of the greatest truths of biology. The and then bores a hole, and greedily pumps up the student who has once seen for himself the facts much-coveted fluid. They have even a more detestwhich I have described, has had their relations ex able habit than this : they seem to delight in taking plained to him, and has clearly comprehended them, refuge in my whiskers, and to rout them from this has so far a knowledge of zoology, which is real and ambush is as difficult a job as that of routing bears genuine, however limited it may be, and which is and peccaries from out a cane-brake, which can only worth more than all the mere reading knowledge of be accomplished by setting the place on fire-a the science he could ever acquire. His zoological stratagem that would in all likelihood prove quite information is, so far, knowledge and not mere as disagreeable to me as the Mosquitoes; in this hearsay.
dilemma I patiently await their movements, and deftly press my finger on every offender as the prick
of the lancets reveals its whereabouts. Now this MOSQUITOES.
suspense, metaphorically waiting for a bite, is
tantalising in the extreme, if you are trying just at “ En avant, Monseigneur Maringouin!”
that critical moment to say something more than READERS of SCIENCE Gossip, permit me to usually impressive to some favoured fair one, and
I make you acquainted with a Madam and distrust the stability of your nerves. Mentally I Monseigneur Mosquito, recently from North- exclaim, “En avant, Madam Maringouin !” bite a western America. At the same time I can assure person with a more delicate skin, or feast upon one you, from a past and painful experience, that an of your own sex, or introduction to them in these pages is infinitely
Try some plump alderman, and suck his blood, preferable to being on terms of greater familiarity.
Enriched by generous wine and costly meat; To obstinate, self-willed, persistently persevering On well-filled skins, sleek as thy native mud, persons, whose sole end and aim is to pester all
Fix thy light pump and press thy freckled feet.
Go to the men for whom, in ocean's halls, with whom they are brought into collision, it is a
The oyster breeds and the green turtle sprawls. common custom,“ down South," to say, “en avant, Monseigneur Maringouin!” Individuals such as Whether the female Mosquito has in all cases the these are for all the world like to Mosquitoes, and same number of lancets, it is difficult to determine. the admonitory warning just quoted is as good as Leuwenhoek says four, Réaumur five, Swammerdam it is truthful. Who ever knew a Mosquito give and Latreille mention six, and there are others who up? Determined obstinacy is the very substance | stand out for seven; but of one thing I am positive, and stamina of its existence. Fret and work your some Mosquitoes are able to inflict a puncture self into a state of irritability bordering upon frenzy, in less time, and of greater depth, than others. stamp, scratch, slap, rub-it is not of the slightest Will any one be bold enough to say, the stab of a use; after every rebuff, the inveterate persecutors summer gnat, or even that of the full-sized Mosonly buzz the more loudly, and stab their blades the quito we are ordinarily familiar with, is inflicted by deeper into one's flesh.
an instrument identical with that which enabled the As regards Monseigneur, we have not much to | "Skeeters” to pierce through the military boots of say: he takes things very easily, does pretty much the Father of the States, in the Jersey marshes, as he likes, dines and sups as best befits his inclina and, if history is truthful in its record of that event, tions-finding amidst the nectar-making flowers caused that usually exemplary man to indulge in bad everything suited to his requirements. Having language, or, as we read it, “swear like a trooper;" paid his addresses to the ladies, and flirted to his or that attacked the army of Julian the Apostate, heart's desire, he grows rapidly old, and very soon and drove him back; or that compelled Sapor, king dies.
of Persia, to raise the siege of Nisibis, stinging his With Madam it is altogether a different affair; she elephants and camels into a state of fury; or that has important duties to perform : publicly, to annoy render the banks of the river Po at some places and persecute every man, woman, and beast within uninhabitable; or, as Humboldt tells us, oblige the
people residing at the mouth of the river Urare to your dress was quite Mosquito-proof you did not sleep in pits dug for the purpose, buried up all but stand a chance, the legions were upon you—thrusttheir heads, which they cover with a rug; and last, ing, humming, and pumping out your blood, despite though not least, that drove the Boundary Commis- all your efforts at self-protection. We used to tie sion, one and all, to quit the prairies and take up our sleeves tightly at the wrists, our trowsers round their quarters in the mountains-stopping the work the ankles, wear thick leather gloves, and a gauze
bag over the head and face, tied in round the throat. The poor dogs suffered frightfully, and would soon have died from the irritation caused by the punctures, had we not removed the animals up into the mountains. During this reign of terror, I started with the Chief Commissioner to visit Fort Hope, about four days' canoe-voyage up the Fraser river; three Indians and the Commissioner's servant made up the crew. The first day we
were terribly beset by Mosquitoes, Fig. 87. East Indian Mosquito* (male) x 8 diameters.
having to keep close to the river of nearly a hundred men. No, I cannot but think bank to gain the advantage of the slack water. the lancet-blades in some Mosquitoes are longer, Each person armed with a wisp of leafy twigs kept sharper, and better fitted to inflict pain, than are up a continuous flogging, to beat down and drive similar weapons in other species. The Californian off our foes. About sundown, we neared a sandy Mosquitoes are not half so bad as the thorough-bred | island, situate in the middle of a wide lake or exBritish Columbians.
panse of the river; landing, and seeing no Mos
quitoes, determined us at once to camp; there being plenty of driftwood, a fire was soon kindled, supper cooked, and preparations made for sleeping. All at once, I suppose attracted by the , fire-light, clouds of Mosquitoes swooped down upon us. There was nothing to be done but to bear it. The Commissioner tried all he could to get a doze, and rolled himself so tightly in his rugs, as to defy
the Mosquitoes to find an entrance; Fig. 58. East Indian Mosquito* (female) x 8 diameters.
vain hope: the pests soon found
a hole, and poured in through it The above portraits greatly resemble à goodly like a crowd to see a pantomime on Boxing-night. number that perished betwixt the leaves of my I could trace the outline of the Commissioner, note-book.
as the pale moonlight slanted on the island, When we were marking the boundary line, writhing about beneath his rugs, as if suffering our camp was on the Sumass prairie, but the from violent choleraic cramps. The Red Men Mosquitoes became so formidable at last that crouched in the smoke, and at short intervals the camp had to be abandoned. It is no ex plunged into the river like seals, to return to the aggeration to state, that the swarms were as smoke dripping wet, and shining as though made of dense as an ordinary fog; and, if possible, more highly burnished metal. I did not try to sleep, but bloodthirsty during the night than in the day. lighted my pipe and paced up and down the island time. Sleeping was utterly impossible, unless one until daylight came, and with it, release from our could manage to shut up the tent so that no Mos miseries. I could recount endless stories of Mosquitoes could gain admission, and then set to work quito adventures, if space permitted me to do so. and kill every one within the canvas prison. Coming The darkies down South relate the following out in the morning was anything but a joke; unless
story, to account for the origin of the name Mos
quito:* From native drawings in the India Museum.
"De white man he come, he settle down, he grow
de corn and cotton; den come de leetle ily-cry , structed that to upset or sink it, is an impossibility. golly! how he bite! Whoop! whoop! white man, One would almost be disposed to think the eggs slap him face, and stamp like mad. He say 'must- were indestructible: though they remain frozen guit-oh!' He shout louder den ebber, and whop | during the winter, they still retain their vitality unde tother side, ‘must-quit-oh!' Den behind, impaired. Many species do not build boats of their den before, dis side, dat side, all de time, 'must eggs; one, I may instance as an example, is found quit-oh! must--quit-oh!'"
in the swamps of the Southern States. The female This is by no means a bad derivation. I felt I sinks a hole in the soft mud with the end of her must-quit-oh! if I did not say it during the tail, and leaves her suspended eggs in the holes by memorable short night on the sandy island. | long slender ropes or stalks. When the larvæ come
Scientifically the Mosquito family belong to the from out the eggs, there is always a sufficiency of order Diptera, family Culicida, genus Culex. The water for their sustenance collected at the bottom of species brought from North-west America turned the hole, and to support life until the time arrives out to be new to science, and was named Culex | for the grub to disappear into the mud therein, to pinguis, because it was fatter, rounder, and more obese undergo its final change. An American writer than any other of its known kindred; the specific speaks of a Mosquito that deposits its eggs in the description is appended as a foot-note. We read sandy plains of the Carolinas and Georgia : “She the following description in Westwood's "Insects," | selects a spot exposed to the fury of the sun, and nage 509, vol. ii., explanatory of the system drops her eggs among the grains of sand. The by which the fly extracts or sucks up the blood : | larvæ, when hatched, must penetrate very deep 6. Taking its station upon an uncovered part of the to obtain moisture. Their proceedings and skin, it lowers its rostrum and pierces the skin by habits are yet to be tested. All you can see is the means of its exceedingly slender needle-like lancets, mother fly dropping her eggs. Twelve or fifteen which are barbed at the tips, and, as by degrees it | days from this time the metamorphosis is complete. pushes these deeper into the skin, the lower lip or Place the hillock betwixt you and the sun as he is sheath, in which they are enclosed when at rest, | setting : the flies ascend in such numbers that you becomes more and more elbowed towards the breast, would think it must be smoke from a boiling spring. until the whole length of the lancets are introduced i These are the genuine 'stingers’ and contain more into the skin. It is supposed that, at the same venom than ten other tribes amalgamated.” time, it instils into the wound a venomous liquid, When the period for the final transformation is at which, while it enables the blood to flow faster, is ! hand, the pupæ float on the surface of the water, the chief cause of the subsequent irritation.” Kirby, and should the day prove bright and sunny, each and Spencer give many interesting and curious pupa case splits, and the little fly with extreme care details relative to the attacks of these insects in and deliberation draws out her front legs from their various parts of the world. The larvæ of the casings. The insect mariner has to be wary now: Mosquito are entirely aquatic, very active, swim- to tilt on one side is certain death from drowning. ming with great rapidity, frequently diving to the Her two front legs are next placed on the water bottom of the water, and again ascending to the (for be it knoirn, a Mosquito walks easily upon the surface.
| water), and the other four bent underneath her body, During this stage of their existence, they undergo | in order to support the boat on an even keel, so to several moultings, to assume the pupæ form. The speak; let the insect but capsize it, and all chance pupæ take no nourishment, although brisk and of righting again is at an end. The wings at this active in all their movements. Space does not stage of the proceedings are wet and lumpy, and allow of my describing the beautiful arrangement would turn the insect over, boat and all, but for the observable in the respiratory systems of the larvæ and support afforded by the bent body and the legs held pupa, but compels me to skip these interesting
| firmly down beneath it; slowly the crumpled wings details, and to refer only and very briefly in con- separate, the air blows freely through them, and as clusion to the system adopted by the female to | the gauzy structures dry, so they become additional insure the safety of her eggs, and the singular aids in maintaining her balance. The long, taper way the mature insect extricates itself from the body now elongates itself, the fragile wings assum pupæ case.
their natural shape, and soon become thoroughly Thefemale Mosquito, when the propertime arrives, 1 dry. The antennæ unfurl like miniature flags, the selects some quiet eddy in a murmury brook, or the feathery plumes (if it be a male) float like pennants tranquil waters of a lake, buoyed up on a leaf or float- in the breeze. Lastly, the legs are drawn fortb, ing spray. She crosses her bind legs and begins build the body nicely poised, then a few strokes of the ing her boat, which, when finished, contains usually | wings are given to test their strength and fitness over four hundred eggs. The eggs nearest the for service. Pausing for a few seconds, probably ends are said to contain the males, those in the to admire its own image mirrored in the water, and middle the females. So admirably is this boat con- to fall in love with itself, as did Narcissus of old,
the Mosquito plies its newly-acquired organs, rises like a fairy into the genial air, and bids adieu for ever to the tiny barque it owes so much to, left to drift away-an empty, useless wreck.
We may not follow Madam's or Monseigneur's proceedings any further, you know them both, I am sure, by the introduction I have given you; more especially Madam : her unwearying solicitations, her ill-manners, and ill-temper, her greed and thirst after blood, her peevish, crying requests-you are familiar with them all, and methinks I hear you say as you lay down SCIENCE GOSSIP, “En avant, Monseigneur Maringouin !”
John KEAST LORD, F.Z.S.
COCCONEIS. TF the figures which we give in illustration of 1 this group are consulted, it will be observed that the valves are elliptical, with a central longitudinal line, and to this character is generally added "and having a central nodule.” It is not always that the central nodule can be clearly made out. This is a large genus, containing, at the least, twenty-five British examples. These are grouped for convenience in two sections : in the smaller of these, the disc is either smooth or striated longitudinally; and in the other, and larger section, the
Culex pinguis, N. S. Fem.-Cervinus, robustus; rostro apicem versus nigro; abdominis pube subaurata, pedibus robustis pallidioribus; alis cinereis, venis fulvis subpilosis.
Sp. Ch.-Fawn colour, stout : proboscis, much longer than the head, and the throat black towards the tip; abdomen with slightly gilded down; legs stont, paler than the body : tarsi darker; wings cinereous; veins tawny, slightly pilose; radial and subapical veins with long forks. Length of the body 34 lines; of the wings, 7 lines. Habitat, British Columbia.
VORTICELLA AND CYCLOPS.-This morning, wishing to mount a few specimens of Cyclops quadri
Fig. 59. Cocconeis major. cornis, I captured some examples with the dipping tube, and transferred them to a small cell about disc has radiating or transverse markings. Both half an inch diameter and a tenth of an inch deep. | our illustrations are from the latter section. CocWhile they were swimming in about four or five coneis major was discovered (by Dr. Gregory in drops of water, I introduced a single drop of pure | dredgings from Lamlash Bay, and though remarkalcohol, which caused wild commotion for a moment,
able, is rare (fig. 59); and Cocconeis nitida was also and in a few seconds-certainly less than half a first found by the same observer in dredgings from minute—the Entomostraca lay dead. After three or the same locality, and also from Loch Fine (fig. 60). four minutes, the cell was filled up by the addition of one or two drops of water, a thin cover put on, and all made secure with asphalte. After two hours the slide was placed under the microscope, when I found that several of the dead Entomostraca bore colonies of Vorticella, or some allied genus, all alive. Every now and then an individual jerked back with the movement generally thought indicative of the seizure of prey, though no living prey were visible, nor would one imagine they existed in this dilute spirit. The Vorticellæ, however, not only existed in the alcoholic bath, but vibrated their cilia and seemed
Fig. 60. Cocconeis nitido, to pursue their ordinary avocations. After five hours some were still living, but many had detached More than half the number of British species themselves from their stalks and lay motionless at were discovered by Dr. Gregory, either in the Glenthe bottom of the cell. When seven hours had shira Sand or the Frith of Clyde and Loch Fine. elapsed, one or two showed feeble signs of life, but It is only our wish in the present instance to indicate after eight hours, the last of the infusoria had de the characters by which the members of the genus parted their lives and foot-stalks. They not only Cocconeis may be known, and not to give a list survived the treatment that proved almost instantly of the names of species which may be found in fatal to the Cyclops, but maintained life for many Mr. Carruthers' catalogue, included in Dr. Gray's hours in the more dilute solution.- George Guyon, handy “Handbook of British Water-weeds or Ventnor, I.W.