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Having made you acquainted with the reproductive organs, we shall be prepared to follow out their functions. As stated, the antheridium at maturity bursts at the apex, and out pass the spermatozoids as a cloud of active particles; the archegonium equally prepares for their reception, the apex of the stylidium ruptures, the edges of the aperture roll back forming a trumpet-shaped orifice, from which we can trace a fine duct passing down to the germinal cell, and more evident now because it has acquired a reddish tinge. Both Hofmeister and Schimper have seen the spermatozoids within this canal.

The germinal cell, now fertilized, immediately commences its own proper development, first downward; perforating the base of the archegonium, it fixes itself in the receptacle or apex of the stem, just as a stake is driven into the earth; then upward to form the seta or fruit stalk, and the contents of the archegonium being thus consumed, its delicate walls are ruptured, the lower part remaining attached to a process of the receptacle, as a little sheaththe vaginula (fig. 265); the upper, carried aloft,

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Closing the mouth of the capsule, we see a little cap-the operculum or lid, in shape flat, conical, or beaked; this, at maturity, is thrown off, either by the swelling of the contents or by the shrinking of a contractile ring of cells interposed between the lid and mouth of the capsule, which is named the annulus; well seen in the common Funaria. In the genus Andreæa there is no lid, and the capsule opens by splitting into four valves (fig. 271); and in another section there is also no lid, the capsule

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becomes the calyptra, or veil, and the seta, having attained its full length, begins to enlarge at the apex to form the capsule.

The Calyptra or Veil envelops the young fruit, and is thin and membranous; it is sometimes torn irregularly, or it remains even at the base, when it is termed mitriform, or it is slit up on one side, when we call it cucullate or dimidiate; it is usually smooth, but sometimes densely hairy (figs. 266, 267, 268).

The Theca or Capsule.-This presents an infinite variety of forms, but all of the greatest elegance; it may be globose, ovate, pear-shaped, or cylindric, straight or arched, erect or pendulous, smooth or

Fig. 271. Schistocarpous Fig. 272. Cleistocarpous fruit fruit of Andreæa. of Pleuridium subulatum.

giving exit to the spores by breaking up from decay (fig. 272). These characters enable us conveniently to arrange mosses in three divisions:

Schistocarpi-the Split-fruited Mosses.
Cleistocarpi-the Closed-fruited Mosses.
Stegocarpi-the Lid-fruited Mosses.

The wall of the capsule consists of several layers

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outer wall of the spore sac, and is a thin plicate, or keeled membrane, divided into processes or cilia, which usually stand opposite the interspaces of the outer teeth, and occasionally 1 to 3 still finer ciliola, occur between the cilia (fig. 275).

Fig. 279. Bifid tooth from peristome of Fissidens. The spores are formed from the cells, filling the spore sac, and are always free from the spiral threads found in the Hepaticæ.

Fig. 280. Peristome and tympanum of Pogonatum aloïdes.

In the above account I have not included the Sphagnina or Bog-mosses, as the views of recent writers tend to separate them as a distinct class, parallel with Mosses and Hepaticæ.

ANTHRENUS.

of the pattern not clearly defined, as the insects are covered with broad scales that form the bands, giving an irregular outline." Woodcuts can scarcely give satisfactory representations of the insects.

WASPS.

THE following communication on British Wasps

appeared in the Gardeners' Chronicle for October 19th::

You published, some little time ago, a letter requesting some of your readers to assist me in procuring a specimen of the nest of Vespa arborea That letter has brought me some kind communications on the subject, but not the nest, which I am still in search of. As the subject has attracted the attention of some of your readers, perhaps you will allow me a little space to explain more clearly what I, with every other naturalist who studies wasps, really do want.

There are seven species of British social wasps, including the hornet. Three of these are tree wasps, distinguished by having the scape of the antennæ yellow in front in both the sexes. Three are ground wasps, in which the scape of the antennæ is yellow in front in the male only. The species are readily distinguished by the forms of the markings on the face, and on the dorsal aspect of the first two rings of the abdomen, as shown in the following diagram:

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THE

HE above figures, illustrative of the paper on "Hairs of Dermestes," page 206, represent the two species of Anthrenus therein alluded to. They have been drawn from well-authenticated specimens, by an excellent authority on these insects, who remarks, "The antennæ in the three common species of Anthrenus have a different number of joints (a curious circumstance in the same genus). Thus in varius, the antennæ seem to be elevenjointed (the normal scheme in Coleoptera), and the club consists of three joints. In museorum they are eight-jointed, with a two-jointed club; and in the very common little claviger (smaller than museorum) the club is only apparently one-jointed. Anthrenus museorum is very indistinctly marked, and a much duller insect than varius, of which some of the bands of lighter colour are spotted with white. scheme of pattern seems alike in both. The edges

The

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1. V. Germanica, the large common wasp, builds in the ground; the case of her nest is made in shelly patches, and is of a grey and white colour.

2. V. vulgaris, the small common wasp, also builds in the ground; her nest being formed likewise in shelly patches, but of a pretty fawn colour, and of a very brittle nature.

3. V. rufa is an earlier wasp than the others. Her nest is of a dull grey, and is built in rings, not in patches. The name of "anchor-faced wasp" has been unfortunately applied to this as well as to the preceding species.

Of the tree wasps :

1. V. sylvestris builds in the ground, or under

eaves, or anywhere; her nest is formed in layers. Every bee-keeper has a word for or against her. She is the owner of the very pretty bell-nests, which have gained for her the name of Vespa campanaria.

2. V. Britannica, Norwegica, or borealis, builds also in layers, which are less regular than those of the preceding species, and generally prefers low bushes.

have the instinct of continuing their burrows until nearly reaching the surface, so that there is only left a slight barrier, through which the perfect insects escape. Westwood ("Mag. Nat. Hist.," Sept. 1834) is inclined to believe that the ticking noise made by the perfect insect is also produced by the larva, whilst gnawing the wood on which it feeds. The larva is figured by Ratzeburg ("Die Forst Insecten," pl. 2, fig. 19, B) and Westwood (Introd., vol. i., p. 269, 11). It is also described by the latter author and by Bouché ("Naturg. der Ins.," p. 187). The larva much resembles that of a small Lamellicorn Beetle, and constructs a cocoon of silky matter, mixed with débris of its food. The wings mentioned in Mr. Athow's letter would appear to be those of a species of Tachina, a dipterous insect much resembling the common house-fly, and which is evidently parasitic on the beetle; at least

3. V. arborea is the blank I wish to fill up. This wasp is found in Gloucestershire and in Savoy. It was first discovered by Mr. F. Smith, of the British Museum, among some firs, on a ridge about four miles north of Wakefield, in Yorkshire. The promise of a reward for a nest of this species, circulated in that neighbourhood, has as yet failed to procure me a specimen to engrave for a work on wasps which I hope shortly to have the pleasure of publishing. If this note shall prove the means of enabling me to complete my series of drawings, II judge so from a cocoon found in the wood sent, shall feel thankful.

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COLIAS EDUSA IN IRELAND.-Having taken a specimen of the Clouded Yellow Butterfly (Colias Edusa) on the 31st of August last at Kilkee, on the coast of the county Clare, I wish to know if it is an uncommon insect in Ireland. Neither my friends nor any of the books I have consulted can inform me if it has ever occurred in Ireland before. -W. B., Ireland.

[It is recorded in "Stainton's Manual" as having occurred in Ireland.-ED.]

WOOD-BORING BEETLES.-One of the principal oak rafters of the roof over the north-east corner of the Triforium of Norwich Cathedral being in a dangerous state, it was examined in order to discover where the rain came through. Some holes were found pierced through the lead, immediately above the decayed rafter, and, on turning up the sheet of metal, the holes were found to correspond exactly with the worm-eaten holes in the oak cladding. Several dead insects were found in the lead, some of which appear to have wings; those enclosed were found in the cladding, and are, I suppose, a species of weavil.-E. A., Norwich.

The insect is Anobium pulsator, Schäll (the 4. tessellatum of most authors), one of our largest species of the so-called Death-watch Beetles. The late Mr. Spence ("Ent. Trans.," vol. ii., p. 11) has given an account of the great injury produced by its larvæ in the timbers of houses at Brussels; and we nave known it to occur in profusion in houses in Northamptonshire, the oak beams being riddled by it. It has been also reared from whitethorn, and appears to remain more than three years before arriving at the perfect state. The larvæ seem to

and from my own experience in rearing other larvæ. The larva of Callidium Bajulus, one of the Longicorn Beetles, has long been recorded as boring through the lead covering of houses, making circular holes. See Westwood (loc. cit. p. 366), and Audouin ("Annales de la Soc. Ent. de France," ii., 76). The larvæ of some Hymenopterous insects have been recorded by a French entomologist as penetrating leaden bullets!-E. C. R.

THE OTTER (Lutra vulgaris).-The breeding season in Scandinavia certainly takes place in February or early in March, and the female brings forth in May from three to four blind young ones. As I have been told from very reliable authority that the otter in England breeds in the winter, I have made very particular inquiries here of men who well know the habits of the otter, and all corroborate the above statement.-Ten Years in Sweden.

WEASEL (Mustela vulgaris, Erx). It has been doubted whether the weasel, like the stoat, becomes white in the winter. I can prove that this is the case from pure white specimens killed in Wermland in the winter. I can also prove by specimens kept in confinement that the change of colour from the red summer dress to the white of winter takes place by an actual change or shedding of the old coat, and not by the old hair changing colour.-Ten Years in Sweden.

A NEIGHBOURLY SPIDER!-A friend writes me: "I was witness this morning of a curious incident. A large bluebottle' having got entangled in the web of a spider, was immediately secured and killed in the usual manner. In this condition-dead and wound round with thread-the fly was deliberately lowered into the web of a smaller spider, who at once seized and carried it off." I never knew, and did not imagine that spiders were sufficiently sociable to feed each other.-Gilbert Green.

LASICCAMPA QUERCUS.-I think the following deserving of notice. Last September, a friend of mine found three larvæ of the above, full grown, and which spun up about the middle of the month. According to the general routine of this insect's changes, the moths should have appeared early this summer. But no; the first one, a female, came out last week, and there are two others waiting their change. Whether they intend to make their appearance this year, or whether they will wait till the more genial summer days, time will show. I do not perceive any difference between this late specimen and those of the usual time.-Richard Tyrer.

HAWK AND WEASEL.-I am indebted to a friend of mine (a keen observer of nature) for the following. Whilst out walking, a kestrel hawk rose at his feet, which attracted his attention by the strangeness of its flight. Instead of its usual hovering, it darted upwards till almost lost to view, when it suddenly descended powerless to the earth. Upon his hastening to the spot he was surprised to see a weasel retreat from the hawk, which was dead, the throat being fearfully torn.-C. Denny, Kelvedon.

QUAIL.-I received a single specimen of this bird some short time since which was shot in this neighbourhood. With us they are extremely rare.-C. Denny, Kelvedon,

LIZARD TAILS.-I think it is not generally known that the common lizard has the power to cast off its tail when suddenly alarmed. I saw a striking instance of this a few days since when collecting insects upon some chalk hills near Beckworth. I have frequently seen these little fellows run without taking their tails with them, when I have attempted their capture, and have mentioned the subject to friends who have expressed their unbelief, stating that it was impossible for a reptile with a tail containing so much substance to have the power to become detached without receiving a severe blow from some hard substance. But in this instance I was in the company of two well-known naturalists when we discovered a lizard. I suddenly placed my hand over it, when up sprang its tail from between my fingers, and, to our astonishment, not only continued to leap about the ground for two or three minutes but crept along with a snake-like motion, and concealed itself in some grass. The tail was divided a short distance from the legs, so that the thickest part was of nearly the same circumference as its body. This appears to be a provision of nature to spare the animal's life, in the event of being surprised by birds or other enemies, the tail being left to satisfy their appetite, whilst the creature takes its departure.-J. B. Waters.

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'ANIMAL GRAFTING, and on the Regeneration of the Spleen in Mammals, and of the Limbs in Aquatic Salamanders," by M. Philipeaux, from 'Annales des Sciences Naturelles," Jan., 1867.

Since the numerous experiments made in 1856 on the extirpation of the supra-renal capsules, the spleen, and the thyroid body, and communicated to the Academie des Sciences, M. Philipeaux has several times observed, in animals which had been operated on some months previously, a new suprarenal capsule, or a new spleen, more or less completely reproduced. He has also, during his investigations, made some interesting observations on animal grafting, and on the reproduction of the limbs of the newt. The following is a resume of the facts which he has recorded :

1. On Grafting the Spleen in Mammals.- After completely removing the spleen from field-mice (surmulots) thirty days old, the organ was returned into the abdominal cavity, and after a period varying from five to ten months, it was found to have grown to the peritoneum at some point, most commonly to the stomach, or on the left side: in one instance only to the right side. The point of attachment was always by the hilum of the spleen, and new vessels were seen to be formed which could be traced to the mesentery. The spleen retained its normal form in some cases; in others became folded on itself, and occasionally was rounded or triangular in form. The structure was found to be always normal; sometimes the spleen had completely disappeared, and not a trace of it could be found, or else a small cyst remained, containing purulent matter. In some cases the spleen was pale and ensanguined, in others very black, and filled with pigment. The animals operated on attained their full development, but were not so large as those which had not been thus treated.

2. On the Regeneration of the Spleen in Mammals. -The first experiments on this subject led M. Philipeaux to believe that the spleen was reproduced after complete extirpation, but this opinion was proved to be incorrect by M. Peyrani, who repeated M. Philipeaux's experiments. The latter instituted a new inquiry, and found that Peyrani's statement was correct that the spleen when completely extirpated is never reproduced; but that when not completely removed, reproduction always occurs. The same remarks hold good with regard to the infra-renal capsules.

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3. On the Regeneration of the Limbs of the Salamander.—M. Philipeaux found that when the limbs and eyes were completely removed, no reproduction took place if the anterior limb, with the scapula, for instance, were amputated, other entire eyeball removed; but if a portion of the eye were left, then regeneration occurred, or if the scapula were left complete, reproduction of all the bones ensued.-L.

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