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very closely, ensuring a compact barrier against the intrusion of insects from without; and the two sets of sepals are placed alternately and are well provided with hairs on their margins.

The ray florets, which present an attractive circle of bright yellow, are unisexual, possessing the female organ only; but this is perfect, and in due time receives the pollen which fertilises the seed, the latter being contained in an achene of semicircular shape at the foot of each floret.

The blossoms are in three parts. Within these is a barren pistil; next, and surrounding it, five stamens joined at the upper part so as to form a tube; and, outside all, a monopetalous five-lobed corolla. The

Fig. 58.-Part section of complete flower.

Its

barren pistil ends in a blunt stigma, of a somewhat pyramidal shape, covered with short spines. office appears to be to raise the pollen by brushing it off the anthers.

The order in which the important organs come to maturity is as follows:- Ist. The anthers discover themselves just above the corolla, hitherto closed. 2nd. The barren stigma is observed gradually thrusting itself upwards till it stands displayed. 3rd. The fertile pistil of each ray-floret shows slightly above the level of the disc and then divides at the top; previously it was concealed between its particular floret and the nearest outside blossom of the disc. To sum up, the disc blossoms mature in regular order, beginning from the outside, and when one or more rows are matured, the fertile pistils become faintly visible. Crossfertilisation is secured by the above arrangement, because, when the first pollen is available, there is no fertile pistil whereon it can be deposited. An insect, therefore, after brushing off pollen, will probably carry it to some other flower, possibly on another plant, where the fertile pistil has appeared.

I am inclined to believe that fertilisation is largely carried on by very small insects that crawl bodily into each corolla in search of nectar; and, inasmuch as they first attack the corollas on the outside of the disc, they are likely to rub their bodies against the fertile pistils. I am confirmed in this opinion by the fact, that the fertile pistils barely disclose themselves above the disc, so that a large insect would rarely if ever touch them. I observed a minute beetle about of an inch long to be a constant visitor, and I have frequently seen it almost bury itself down a corolla.

No doubt its action had the effect of pushing down the anthers and thus helping the stigma to rise. I think that, if it were not for these insects and others acting in a similar manner, fertilisation would never take place. Again, the formation of the entire flower is in favour of the supposition, that small insects alone are concerned in the important process; for, if the duty had to be performed by large ones, it is most likely that each blossom would have been a perfect flower, and then a large insect when thrusting its proboscis down the corolla would, at the same time, press against a fertile pistil. The habit, too, of the complete flower closing up at night points in the same direction; for many large moths fly about then, and their attentions, far from being serviceable, might be positively injurious, as they would, but for this, remove pollen without placing it where required.

The barren stigma is a singular feature. It is an instance of how a part may be made to subserve a purpose for which it was not originally intended and modified to suit the surroundings. Without the assistance of this barren stigma, it is doubtful whether pollen would ever be separated from the minute anthers and raised to a position to be available for visiting insects.

The figure represents a part section of a complete flower, magnified about four times, with only three blossoms a ray floret and a bract left standing, by which some idea may be gained of the method of fertilisation.

224 Camberwell New Road, S.E.

NOTES ON TRIFOLIUM STELLATUM.

'A'

MONG the improvements of the last edition of the London Catalogue of British Plants' is the inclusion of such of our non-native plants, as are now thoroughly established and look quite wild.” Some of these formerly denominated as "casuals" are thus very properly admitted to our Flora. Mentioning the starry-headed trefoil to a botanist at Kew as occurring at Shoreham, a friend was recently told that it was formerly to be found there; but had long since disappeared. This, I am glad to say, is by no means the case, for on the low line of shingle near Shoreham Harbour this lovely plant exists in profusion. As confined to Sussex, and as having been established in its present locality for nearly a century, a few observations on it may be offered. How it gained its footing on this point of the south coast, and there only, is unknown. The seeds may have been scattered from some wreck, or imported in some of the curious modes of plant distribution described by Darwin. Gerard appears to have been acquainted with it in the sixteenth century; for, speaking of Bauhm's Trifolium stellatum, he says "for distinction's sake, I adde hirsutum, calling it Trifol, stellatum hirsutum," and his description of it is so quaint and

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crimson hue. Freshly gathered specimens (May 24, 1888) show albino flowers, mingled with others of pretty pink, in the heads curved before expansion. Some of our wild flowers are of especial interest as being confined to but a single spot in our island, and of these a sad diminution has sometimes taken place owing to accidental circumstances, or the ruthlessness of collectors. It is to be hoped that such may not be the case with this floral gem.

F. H. ARNOLD.

NATURAL HISTORY JOTTINGS. THE GREEN TORTOISE BEETLE (Cassida viridis). [Continued from p. 138.]

August 28th.- This evening, which was dull, moist and mild, I took from a thistle three tortoise beetles that had squatted on the centre of the leaf above, near its junction with the stem. From their colour assimilating closely with the colour of the leaf they were not readily distinguishable, their antennæ and limbs being tucked away beneath the leaf green carapace which entirely covers and conceals the black head and body; they were just like so many green scales lying on the leaves. The surface of the leaves was very much blotched by having had the parenchyma eaten out from above in small irregular patches, and the lower epidermis left intact; and as the tortoise beetle itself eats out the flesh or parenchyma of the leaf (as I have already observed in those evolved within doors), as well as it does its larva, though in a more irregular manner, I am inclined to think that it has been the agent of this state of the leaves on this particular plant.

As I have taken the imago from the foliage of thistles as early as June 25th, and again on July 20th, and the full-grown larvæ (accompanied by younger larvæ) not before the second week in August, it would appear that the tortoise beetle hybernates in the perfect state; when we consider that all those larvæ of the August brood are fully evolved in the autumn, and that the food-plant (should the agriculturist allow it to stand and shed its seed) will die down in the winter, and thus furnish no supply of food to hybernating larvæ of a later brood.

In all its stages the tortoise beetle is well supplied by nature and instinct with the means of concealment and defence. In the perfect or imaginal condition, its form, structure, and colour are such that it can apply itself closely to the foliage of its food-plant, and bear a near resemblance to a green scale (itself not readily distinguished) lying thereon. In the larval condition, its colours are dingy; it is over-shadowed by and concealed beneath its coarse black fecal canopy, which causes it to closely resemble the mutings of those insectivorous birds that affect its haunts; and its low depressed body is completely surrounded by an armament of strong setose lateral spines, which

will tend to keep insect foes at bay, and with the hard rough fecal covering it will probably cause birds that may once feed upon the armed larva to consider before again swallowing a morsel that contains more hard, prickly, and innutritious husk than juicy, nutritious kernel. In the pupal condition, the colours are again dingy and dark; the thorax and anterior exposed part of the abdomen are still closely surrounded by spines, whilst the last four segments of the abdomen are encased in the run-together exuvia of the anterior portion of the larva, and thus more densely than ever surrounded with setose spines; and the posterior portion of the exuvia, embracing the six hindermost abdominal segments, is thrown up tensely and vertically, and the anal appendages are thrown apart fork-like and horizontally forwards over the dorsum, by the long fine rigid and elastic anal appendages of the pupa, the whole constituting a densely spinous and elevated anal protection and tail to the insect during this its most helpless stage of existence. Moreover, when even lightly touched, the pupa has the power and habit of suddenly throwing itself up vertically in its anterior three-fourths, and of retaining that position at pleasure. This feat is rendered possible by the manner in which the pupa is secured and retained within and by the larval exuvia the setose spines of larvahood appertaining to the sixth, seventh, and eight abdominal segments, are now, in the pupa, reduced to mere ridges, and a simple short spine backwardly directed, while the anal appendages (the modified spines appertaining to the ninth and last abdominal segment) are reduced to two long, slender elastic spines; the former, probably, by an outward pressure, aiding in retaining more firmly the hinder portion of the abdomen within its exuvial sheath; the latter, undoubtedly, being the main instruments in mooring the pupa, and sometimes visible within the tensely elevated exuvial tail bent back bow-like; whilst the abdominal exuvial disk remains firmly glued to its seat, and prevents the pupa falling forwards.

Kirby and Spence, in their "Introduction to Entomology," in speaking of the genus Cassida with respect to the remarkable habit of its larvæ in sheltering themselves under a canopy formed of their own fæces, have the following remarks: *In some species the excrement is not so disgusting as you may suppose, being formed into fine branching filaments.. This is the case with C. maculata, Linn. In the cognate genus Imatidium, the larvæ also are merdigerous; and that of I: Leayanum, Latr., taken by Major-General Hardwicke in the East Indies, also produces an assemblage of very long filaments, that resemble a dried fucus or a filamentous lichen." Again, J. O. Westwood, in "An Introduction to the Modern Classification of Insects," says: "The larvæ of some of the exotic species of Cassida (C.

Vol. ii., p. 212; ed. 6th, 1843. Vol. i., p. 379; ed. 1839.

ampulla, Oliv.), as well as those of the genus Imatidium, are also merdigerous, producing an assemblage of very long filaments, resembling a filamentous lichen. The late General Hardwicke published an account of the transformations of a beautiful East Indian species of Cassida. . . . The larva closely resembles my figure of that of C. viridis; but the lateral rays are much longer, and anal feci-fork much shorter."

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Now, so far as the British species of Cassida are concerned, the fine branching filaments" into which the excrement was supposed to resolve itself, are in all probability simply the exuvia of the branched or setose spines constituting a goodly portion of each section of the fecal canopy, and a much larger proportion of the newly added exuvial platform for its continuation or increment; whilst with respect to the exotic species, as the "lateral rays (spines) are much longer, and the anal feci-fork (anal appendages) much shorter," may it not be possible, nay probable, that the "assemblage of very long filaments, resembling a filamentous lichen," is simply the exuvia alone, the superaddition of the fæces being unnecessary and undesirable, since the "anal feci-fork is much shorter," and is probably less well adapted for carrying a load of fæces that shall entirely extend over the body of the larva, while the exuvial platform will be larger and more extended, and consequently more protective, owing to the much greater length of the lateral rays or spines.

In the British species of Cassida, a protective fecal dorsal covering being necessary to the wellbeing of the larva, the reason why it should be elevated above the body, and borne as it is on an organ specially modified for the purpose, rather than the fæces laid directly upon the dorsum (as naturalists inform us is the case with the larva of the Crioceris merdigera), is obvious enough; the spiracles of the flattened larva are situated dorsally, and from the nature of the fæces would at an early period in the existence of the creature become clogged up, and asphyxiation would assuredly ensue; and thus the very means employed by the larva as a protection and self-defence would be converted into a means of selfdestruction. This necessity for a self-provided dorsal covering has involved a considerable and remarkable modification in form and direction of the two spines appertaining to the last abdominal segment of the larva, and of the terminal portion of the alimentary canal or intestine, as well as in the direction or pose of the posterior portion of the body; thus the spines are enlarged, completely changed in direction (being vertical instead of horizontal), and are furthermore thrown forwards horizontally over the body by the singular carriage of the hinder portion of the abdomen, while the anus, instead of terminating horizontally with the body, is projected far beyond it vertically by an extensive telescopic elongation of the intestine and the erection of the extremity of the body.

It seems somewhat singular that (from Kirby and Spence downwards) our most distinguished and practical naturalists, our instructors and authorities in entomology, who have been attracted by this most remarkable larva and have written about it, and most, if not all, of whom must have handled it, should have missed the true formation and constitution of its artificial dorsal covering; and should have entirely ignored the wonderful modification in form and function of the terminal portion of the intestineits exsertion, and its prolongation telescope-tube-like and evagination on the passage of the feces; its remarkable mobility which enables it to assume the most varied forms, and thus to be applied over the entire extent, the length and breadth, of the exuvial platform, so as to suitably dispose the fæces in the construction of its singular canopy; and, lastly, to be used almost, as it were, as an organ of prehension, in aiding in the disposition of the exuvial platform, and in the displacement of the canopy at the close of the larval period. Burmeister, when treating of the artificial coverings of the larvæ of insects, useful as a protection from their enemies, has, at page 506, the following remarks: "We find other coverings in the aphide and tortoise beetles, which envelope themselves with a white woolly or fibrous substance, the origin of which we are not yet acquainted with, but it appears to be produced by a peculiar secretion of the skin."* Thus this author even classes the artificial exuvial and fecal canopy of the larvæ of the tortoise beetles with the natural woolly clothing of the aphide, which is certainly an outgrowth from the body of these homopterous insects in all their stages. CHARLES ROBSON,

Elswick, Newcastle-upon-Tyne.

LUNDY ISLAND.

By DR. CRESPI.

ISITORS to Instow and Ilfracombe generally

VIS

sooner or later are fortunate enough to catch a glimpse of a long, low line far away on the western horizon: that is the tiny Island of Lundy. At a distance of twenty-four miles, it seldom looks more than a nebulous line, slightly raised above the water; but on near approach it is seen to stand up grandly-a vast granite mass, four miles long, three-quarters of a mile wide, and from four hundred to, in one place, over five hundred feet in height. Its configuration is singular; its long diameter points nearly due north and south, while its eastern slopes, precipitous enough to make them interesting and remarkable, are only one degree less striking than its western sides, where walls of rock rise in perpendicular steps sixty and eighty feet at a time. The western side is particularly imposing; and were Lundy more accessible, it would attract tens of thousands of visitors. But Lundy has

* Manual of Entomology, transl. by Shuckard : Lond. 1863.

no harbour at all, and no landing pier or stage whatever, and though the beach, at its south-eastern end, is good as far as it goes, it is not always accessible or safe. Sometimes furious seas roll upon that beach, as though they would wash the island away, and Lundy is then completely cut off from all connection with the mainland, except by telegraph, which of late years has been laid down between Hartland, on the Devon coast, and the south point. Off Lundy the anchorage is excellent in westerly gales, and then, especially if the storm lasts some days, large numbers of fine steamers and splendid ships with whole fleets of skiffs and tugs take shelter under the lee of the island, until, with a shift of wind to the east, they are off to a less exposed spot.

I once lived on Lundy for three years and a half, and after a long residence in great cities and much hurrying to and fro, the contrast was startling. Quiet and leisure I had in abundance; but, cut off from the conflict and competition of life, the inclination to work and to turn my time to the most profitable uses was wanting, and never did I do less, never did I get through fewer books. No! whatever poets may say, the man exposed to the storms and distractions of life works hardest and does the best work. Rural retirement is more fascinating to the imagination than in reality. I used to listen to the piercing shriek of the restless wind, stroll about the island, exchange a few words with the residents, and when evening came I was quite tired enough to feel that I had earned a good night's sleep in return for my arduous labours.

Lundy is in many ways singular; its chief attractions are its configuration, climate, bird-life, and vegetation : to say nothing of its history: not very eventful it may be, but extending far enough back to invest it with some interest. On the south point, overlooking a narrow and dangerous neck of land, connecting the greater mass of Lundy with Lametry, stands a small castle, rugged, ancient, and gloomy, once the stronghold of a Norman baron, and still called "The Castle." Its original lord and builder was a certain De Marisco, which is said to be a corruption of De Montmorency. The island, according to tradition, was granted, centuries ago, to the Knights Templars, who, however, never took possession of it. Then it passed from noble to noble, was the scene of much fighting between Welsh and Irish, and finally, fifty or more years ago, came into the possession, by purchase, of the late William Hudson Heaven, a quiet, amiable country gentleman, who made it his home for years, and there died a few years ago. The present owner is his son, the Rev. Hudson G. Heaven, M.A., formerly of Trinity College, Oxford, an able and accomplished man of scholarly tastes, who has the rare felicity, in the south of England, of being absolute lord of all he surveys, without an equal or rival within many miles.

The top of the island is an extensive and tolerably level plain, sloping somewhat towards the north and east, with no trees, no hedges, and no shelter. This

want of shelter is a serious drawback, and from the comparative mildness of the winter and the absence of severe frost, were there only substantial protection, large quantities of excellent early vegetables could be grown for the Bristol markets. Perhaps, were sufficient expense incurred, a good deal of shelter might be made amid the combes on the eastern slopes, and vegetables of excellent quality could be grown a month earlier than on shore. After the end of March, white frost is extremely rare. In March, 1878, the lowest reading was 32° F. and in April 33° F., and in May 39°5. In March, April, and May, 1879, the readings were respectively 29°.5, 30°5, and 36°5 F., and in 1880 in the same months, the minima recorded were 36°0, 39°0, and 38°5. Unfortunately the elevation of the island and the want of shelter from the winds, in some measure counter-balance the signal advantages which the absence of low temperatures would give the island.

The south half has long been cultivated; there the grass is smooth and green, and the crops of superior quality; the northern half is, however, in a state of nature, with shallow soil or bare rock, and more lichen and moss than turf. The slopes of the island, locally called sidelands, are, however, in places singu larly beautiful and attractive; in others, principally, though not wholly, on the west, they are majestic and impress the few people who have an opportunity of seeing them as sui generis. On the slopes, well under the shelter of the mass of the island, and at some distance above the water, the soil is, in places, deep and contained in pockets, where it has accumulated, and there the grass and many species of wild flowers luxuriate, and attain splendid proportions. The speciality of the island is its wild birds, which once abounded in millions. In those days, when they rose, they filled the air with discordant cries. Long, however, before I took up my residence on the island their numbers had greatly diminished, and though protected, as much as possible, by the squire and his sister, serious inroads have been made upon their numbers, and they no longer rise in the dense clouds reported by earlier visitors. In April the sea birds come in, and speedily almost cover the rocks and the more inaccessible headlands and a little later

they commence to lay. The chief species are several sorts of gulls, guillemots, shags, razor-billed auks, puffins, and a few, only, alas! very few gannets, that noblest of British sea birds, darting along like a ray of light far beneath the spectator's feet and not much above the water. It is said, though I cannot vouch for its truth, that Lundy is the lowest latitude in which the Solan goose lays, though Dr. W. F. Ainsworth has seen it flying along in its characteristically majestic fashion, on the coast of Portugal. These sea birds choose open ledges, and most of them, almost of necessity, lay their eggs where daring climbers can get to them. The temptation is too great, and as the work of destruction never

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