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SKELETON OF PURPLE URCHIN.
(Echinus lividus). MHE Purple Urchin of our shores is so common
1 an object that few, if any, of my readers-scientific or otherwise-can have failed at some time or other to have seen and admired it. Not many, however, I believe, who have seen it know-to use a hackneyed but expressive phrase-what a world of wonder is wrapped up in its prickly box. A little of this wonder I propose to reveal, confining myself, however, entirely to its skeleton. To commence with the shell or test, as it is called : This is made
to the smooth surface of the glass or stones. Each of these suckers is terminated by a dise, the skeleton of which presents the same calcareous network as the shell, but in a more beautiful and symmetrical form. Fig. 62 gives a magnified representation of this ambulacral disc, as it is called.
In many foreign species of Echinus the spines, when examined in section under the microscope, present a very beautiful appearance, somewhat similar to that of exogenous wood. This appear. ance is produced by successive rings of open spaces and solid pillars, which mark the yearly growth of the spine.
Although the spine of Echinus lividus does not present this beautiful ringed appearance, doubtless, as bas been suggested, from its being the result of only one year's growth (being exuriated and reproduced annually), still it presents a very striking appearance. It is, in common with the species of other echini, composed of solid calcareous ribs, alternating with bands of an open calcareous network.
Fig. 61. Portion of Shell, x 230.
Fig. 63. Transverse Section of Spine, x 60.
These ribs and bands in section appear as alternating rays, and the network being coloured purple, they are very striking. Fig. 63 represents a transverse section of the spine, and exhibits the alternating bands of solid ribs and open network.
Attached by a peduncle to the spines are to be found the curious bodies called Pedicellariæ. These, at one time supposed to be parasites, are now generally considered as simple appendages to the spine, although their function is somewhat doubtful. Each of these consists of a thin calcareous stalk, surmounted by a curious pincer-like apparatus, the whole being invested by the general animal membrane of the Echinus. Fig. 64 represents the head of a pedicellaria. The pincers are double, and are formed of a fine calcareous network, resembling that of the shell. The edges of each limb of the pincers are serrated.
Thus much for the external portion of the skeleton. Internally, the only part of the animal requiring
Fig. 62. Ambulacral Disc, x 180.
Every one who has ever kept an Echinus in the aquarium alive must have noticed its mode of locomotion-how it protrudes from orifices in its shell sundry curious suckers, by means of which it clings
the support of a skeleton is that connected with the movements of the teeth and jaws.
This oral skeleton consists of the teeth, the plates to which they are attached, and the processes for the attachment of the muscles. From its curious form it was compared by Aristotle to a lantern, and hence is now often called the Lantern of Aristotle; it is a well-known seaside specimen. The teeth resemble somewhat the front teeth of a
tubuli of bone or dentine. This is caused by the different portions of the tooth being more or less closely cemented together by minute particles of calcareous matter, which bear the name of the "soldering particles.” Thus a longitudinal section of the tooth presents somewhat the appearance of bone with its lacunæ, canaliculi, and laminæ. The edge of the chisel-shaped portion of this tooth is coated with a layer of enamel. The tooth is shown in longitudinal section in Figs. 65 and 66.
The plates and processes of the “lantern” partake of the general network structure of the shell, and therefore call for no particular remark.
THOMAS GRAHAM PONTON.
HARDY FOREIGN FERNS.
1 foreign ferns are there, which could be obtained at a nursery, and which would succeed in an open-air fernery? It shall be our endeavour briefly to enumerate those of which we have any knowledge, with a few of their characteristics interspersed, so as to redeem our notes from condemnation as a mere list. It may be premised that April or May is a very good month in which to transplant ferns, and therefore a few hints will be opportune. Need we repeat the caution that if ferns are to succeed they must not be planted in too dry a spot, or much exposed to the sun. A shady sloping bank, and good specimens will soon result in a good fernery.
rodent; they have the same chisel-shaped form, but they have an addition in the shape of a keel which runs along the back. If a longitudinal section of one of these teeth be examined, it will be seen to bear a striking resemblance in its structure to the teeth of the higher animals.
The keel is composed of rods of carbonate of lime, lying obliquely to the axis of the tooth. The chisel-shaped edge consists firstly of a series of triangular calcareous plates, called the "primary plates ; " these constitute a framework with which the other parts become connected. To these plates, at some distance from the base, are attached a
Fig. 67. Ostrich Fern.
The Royal Fern is a great favourite, and so would
be its foreign relatives if they were better known. series of lappet-shaped laminæ, called by Mr. Salter The Cinnamon Osmund (Osmunda cinnamomea) from the "secondary plates.” To these again are added a North America, is equally beautiful, and quite disthird set of appendages named the “flabelliform | tinct in appearance. So also is Clayton's Osmund processes ; " these last consist of reticulations of (Osmunda Claytoniana), another hardy North Amecalcareous fibres, having a fan-shaped termination. rican species. Either of these would lourish in the The flabelliform processes are succeeded nearer the open air, and prove a great acquisition to any one apex by an appearance closely resembling the with room to grow them.
The prince of hardy exotics is the Ostrich Fern The Maiden-hair Fern is often made the subject (Struthiopteris Germanica), which is not half so well of complaint that it is too delicate for the out-door known as it deserves to be. The erect pale-green fernery, except in the extreme south. Such comfronds, abont two feet in height, stand around the plainants ought to know that there is a North crown like the feathers in a shuttlecock, forming an American species, equally beautiful, easily grown, inverted cone. Every one who'aspires to an out-door | and more hardy than the European Maiden-hair. fernery should obtain this species, which is as hardy This deserves the name of Hardy Maiden-hair, but and easy of cultivation as the Male Fern.
it is known to gardeners and nurserymen as Adiantum pedatum. There is also an Australian species (Adiantum assimile), but it is not more hardy than the indigenous species, and very much resembles it in size and appearance.
Fig. 68. Virginian Fern (Woodwardia Virginica).
Fig. 69. Onoclea sensibilis. There are also two North American ferns, belonging to a genus of which we have no British representa A very commonly cultivated fern is Onoclea tive, with fronds about eighteen inches in length. sensibilis, with fronds two feet in length, and with These are the Virginian Fern (Woodwardia Virginica) the fertile and barren fronds differing in form. and the Florida Fern (Woodwardia areolata). They There is no great care required in its cultivation, are both of them hardy enough to stand the winter and its appearance is very different from any other out of doors.
hardy fern. Our own Lady Fern is so beautiful that a know. Another genus which has no representative ledge of it is sufficient to induce any one to pur amongst British ferns, furnishes a hardy species with chase a Lady Fern on trust, and if it should be a character somewhat resembling the Marsh Fern. Michaux's Lady Fern (Athyrium Michauxii) they The fronds are about two feet in length, and its will not by any means be disappointed. This North name nearly as long, if written large enough; this American species does not attain more than half the is Diplazium thelypteroides. size of the British, which perhaps is in itself a re. There are also two species of Buckler Ferns commendation.
belonging to the same genus as the Male Fern, Amongst the Spleenworts there is a hardy species which are certainly hardy enough for out-door which may be called the Narrow-leaved Spleenwort | culture. One of these is a native of China, and is (Asplenium angustifolium), which may be grown on known as Lastrea decurrens; the other is a North a rockwork out of doors.
American species called by cultivators and botanists
Fig. 70. Siebold's Fern (Lastrea podophylla).
Fig. 72. Cyrtomium falcatum. endure the winter's frosts unbarmed.
Our two rare little Woodsias have representatives It is the more desirable as it serves to illustrate a in the United States and Mexico, with fronds one genus of which we have no indigenous species. foot and upwards in length. The Mexican Woodsia. It is quite possible that some species has been
omitted which is equally hardy, and equally worthy with the foregoing for out-door culture; but we bave named sufficient to prove that an excellent collection of exotic ferns may be grown out of doors, many of which are pro
bably unknown to amateurs. It POINT
has been a necessity to employ the botanical names, because without them it would be very difficult
to order them from a nurseryman, Fig. 71. American Shield Fern (Polystichum ucrostichoides).
should any of our readers be so
disposed. The majority of the (Woodsia mollis) and Perrin's Woodsia (Woodsia | above are too large to be grown in a closed obtusa) are both hardy, and very desirable for an case. The woodcuts illustrate the fructification, open-air fernery.
but hardly give any idea of the appearance of the Finally we might commend an American Shield | fronds.
think, really efficacious; but here children make use RURAL NATURAL HISTORY. of a sort of charm when applying it, sayingM Y friend “B.” will, I hope, pardon me for
“Dock go in, nettle come out.” "cribbing" the title of his interesting paper Is it possible that a grain of truth may even be in the April number of the SCIENCE GOSSIP; but I found in the following superstition? If a lock of do so, because I am going to write upon the same human hair should be thrown out of doors, and a subject, and because if some of our correspondents toad should happen to get it entangled round its in different parts of the country were to collect the leg, the person from whose head it came will have curious and superstitious remedies that are in vogue perpetual headache for the rest of his life. What a in their neighbourhood, and the strange ideas about | dreadful contingency! plants and animals that prevail amongst the people, It is considered very unlucky to cut a child's nails and were to record them under the same head, what during its first year; and Cheshire mothers are very a book full of amusing-perhaps, now and then, of careful not to do so, lest it should cause the child instructive-matter we should have! It would be to be "light-fingered." We should think it would interesting to find that the same things were be be a good deal lighter fingered after a twelvemonth's lieved in remote places; more interesting still to growth of nail was cut off. trace them to their origin, and find the one grain of truth that very often really exists, and has served finger, which is supposed to be venomous. as the foundation upon which a fantastic structure Freckles on the skin are called “ fawn-freckles," of ignorance and error has been built. Since I and are supposed to come at the same time as, and wrote about “Strange Remedies," in one of the be in some way consequent on the building of birds' early numbers, I have met with many more that are nests. Is this because so many eggs are spotted curious, and many I had already collected, but with brown? or are the spots on the skin and those whether peculiar to Cheshire or not, I cannot tell. on eggs supposed to be caused by the same influ
We have three infallible cures for whooping- ence, whatever it may be ? cough, or, as it is called, “ Chink” cough. (The A child during its first month is supposed to see drawing in of the breath in laughing is also called, | all that is to happen to it through life. If it laughs “Chinking.")
much, it is a sign that its life will be happy. Every Receipt No. 1.-A lock of hair is to be cut from one must have the “frog” (thrush) once in his life. the back of the head of the child that is suffering | If not in infancy, then certainly before death. I from the ailment. A hole must be bored in the may remark that in books this disease is called stem of a wicken tree (mountain ash), the lock of thrush or “throg," and tbat" frog” appears to be hair stuffed into it, and the hole be plugged up a corruption of the word “throg.” It may be, howagain. The patient will sometimes recover in two or ever, not unlikely that "frog” is the older word, three days. That the charm may work well, how and " throg" the corrupted pronunciation. In the ever, it must be done secretly, or, as we should say same way many of our country people call thistles, in Cheshire, “unbeknown," and the charmer must fistles," as if derived from the Latin " fistula." If not be the father of the child; any one else can per this be the true derivation, it shows that the name form it.
“fistle," in common use still, is as old as the time of Receipt No. 2.-A woman whose married name the Romans in England; and I am inclined to think is the same as her maiden name has the gift of that it also shows us that the Romans had local curing whooping-cough. She has simply to give names for plants, “ fistula” being a local Roman the child something to eat or drink (it is generally | name for "carduus," the classical word for thistle. a “sugar butty") and it will get well. I have a It is thought to be very unlucky to have money neighbour who married her cousin, and did not bidden for anything, especially a live animal, that you change her name, who, I believe, thus practises. I do not wish to sell. It is sure to go wrong in some
Receipt No. 3.-A portion of hair from the cross way or other. This, however, is a general belief, on a donkey's shoulders is in great demand, and is and not, I think, confined to Cheshire. thought to be very efficacious; and very lately a | Bees should never be bought, or if bought, should man came to our house, and begged some from a be paid for in gold, otherwise they will do no good. donkey that our children ride, in order to cure liis They should be either begged, or borrowed, or child. The hair is wrapped up in flannel, and the
stolen. It is the custom in Cheshire, when any one flannel sewed round the child's neck, and it is sure wishes to begin bee-keeping, for some neighbour to get well.
who already keeps bees, to give him a swarm, with In the article upon “Rural Natural History," the understanding that it is to be paid back if reabove referred to, "B." speaks of the dock being quired. I have, however, seen bees bought, and for used in Buckinghamshire as an antidote to the a good deal less than gold, and I recollect an amus. sting of the nettle. It is also used here, and is, I ing episode happening at a sale, where an old woman