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and P. mammillaris. The first has the central part | British Museum. To whichever jaw this dental
of the tooth not much raised, with the transverse
ridges all insensibly merging into the surrounding
granulated area; in the second (fig. 82), the trans-
verse ridges and furrows are coarser and mostly bend
round on reaching the granulated area, producing
gyrations suggestive of the specific name; in the
third (fig. 81), the central part of the tooth is raised

armature belonged, its arrangement is obviously very
different from that of Cestracion, and if we were now
venturing upon innovations, instead of simply
recording the present state of this branch of Palæonto-
logy, we should remove Ptychodus altogether from
the Cestraciont family, and endeavour to find a place
for it in proximity to some of the Rays.

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MY GARDEN PETS.

By E. H. ROBERTSON.

PART II.

PRING-TIME is particularly disastrous to my

SPRIN

pets. Tempted by the bright sunshine they roam to distant pastures, to provide for the wants of a daily increasing family. After a night's rest and refreshment, they issue forth full of energy, and without impedimenta, but return later in the day tired and heavily laden, to be cut down on the very threshold of home, by the cruel, biting wind, thousands of the weary labourers being thus sometimes lost. To a lover of bees it is distressing to see the ground strewn with their chilled carcases, and, as I never pass a chilled bee without making an effort to warm him into life, I gather mine into a bell glass, which, inverted over a stand, I place before a fire. I may have collected but a score, perhaps it contains 500 or 600. Soon the inert mass shows signs of vitality—here and there a tiny leg or antenna quivers, a silvery wing shimmers in the flickering firelight, a few moments later and sundry pollen-laden little fellows may be seen brushing their coats and wings, and loudly buzzing, as they scamper up and down the side of their prison, in search of some means of escape, and soon nearly all are astir. Turning the glass mouth upwards in the open air, the thoroughly resuscitated fly off to their hives, a few not yet fully recovered, after a short flight, descending to the ground, to be returned to the glass, rewarmed, and fed with honey until fully restored. Sometimes every bee may thus be brought back to life, but more frequently a small proportion (say from five to twenty per cent.) are not to be so easily restored; they are almost invariably the old and worn out, quickly recognised by their black, hairless bodies, whose slender thread of life has been severed by the north wind's keen edge. If apparently drowned bees be placed upon a blotting pad, and thus treated, the genial warmth will almost certainly revive them.

To a person not familiar with bees the statement that the sounds emitted by them are as varied, and as expressive of fear, anger, pain, &c., as are those of human and other animals, may seem incredible; it is, nevertheless, strictly and literally true, and the ear of the experienced apiarian, or observant naturalist, soon learns to distinguish them. There is not a greater difference between the soft purr of the contented puss, and her threatening growl when tearing her prey, her pleading "mew," and her diabolic caterwauling, or unearthly sleep-disturbing yell, than there is between the droning hum of the tired homing bee, and the fierce threatening buzz which warns the intruder to decamp.

The crisp whirr with which the active little fellow springs from the threshold of his hive into the regions

of light cannot pass unnoticed, and the delightsome hum which expresses his happiness, as he circles and shoots to and fro, when the cloud-dispelling sun cheers him into activity, is pleasant indeed to him who loves such rural sounds. Ilis pathetic cry of distress, too, when unable to extricate himself from the cruel grip of a spider, or has been accidentally squeezed beneath some weight, calls for the ready help of him whose ear is alive to the cry of pain. This diversity of cries alone should teach the novice when to avoid proximity to bees' quarters; but as there is an art in seeing, so is there in hearing, and some there are who never learn, and if they have anything to do with bees they soon pay the penalty of their ignorance.

Dear reader, have you ever witnessed the contortions of a terror-stricken bee observer? If not I can promise you an entertaining sight, and even if you be an unfortunate wight upon whose liver that most baleful of all subtle malignancies-the east wind-has laid its firmest hold, it will most assuredly provoke your mirth. It always reminds me of the mechanical figures which the cockney void of taste erects upon a post or staff in his small garden. The figure gyrates upon a pivot, and every breath of wind sets in rapid motion, windmill fashion, two fin-like appendages, that are supposed, by a wide stretch of the imagination, to resemble arms. See but the terrified one as he wildly smites the air in his futile efforts to beat down his puny foe, and the inanimate figure will present itself to the mind's eye. His ludicrous antics can have but one effect. The bee, perfectly innocent of mischief, naturally enough believes itself to be the object of unprovoked attack, and, resentful, makes short work of his enemy, and if the latter escape scot free his escape is due either to the thickness of his garments, or, more probably, to the hastiness of his retreat. It may be stated that, as a rule, bees never sting when roaming, nor even close to their homes, unless irritated by the recent plunder of their store, or disturbed by the passing and repassing of any person in front of their hives.

Perhaps there is nothing that more readily excites a bee to anger than the latter. The term vicious, so often applied to bees and wasps by the ignorant, is a senseless misnomer, and although there is probably as great a diversity of disposition to be found in any one bee community as amongst the individuals of other races, they are most certainly not aggressive, and the notion that they sting of malice prepense is an absurd one. Even a stranger may, with impunity, stand before a hive when bees are returning home heavily laden, and although his garments may be thickly studded with the weary little labourers, not one will molest him, nay, if the tip of the finger be presented, the tired insect will almost invariably accept the proffered aid. Let the stranger, however, beware lest some watchful sentinel dashes at some unprotected part of his person.

When beekeepers are standing near hives, single bees very frequently make close examinaiion of the intruder. I am constantly the object of their close attention. Perhaps the little examiner is but passing away a spare moment by way of recreation, probably, mistrustful, he is warning me to give his home and friends a wider berth. First he buzzes within an inch of one eye, then visits its fellow, then makes a tour of inspection, sounding his trumpet first in one ear, then in the other, his observations being almost entirely confined to the head. When I hear his threatening buzz, knowing that he is not to be trifled with, and wishing to spare his life, I close my eyes and remain quite stationary, and, after awhile, my little friend, seeing that he has nothing to fear, settles usually upon my face, sometimes the lobe of an ear, more frequently the tip of my nose, and after a few preliminary brushings up pursues his peaceful way, and I mine. We have become better acquainted, and he is far less likely to trouble me on any future occasion, whereas a timid person would, by his frantic fears, provoke a catastrophe. His terror may perhaps be excused, when it is remembered that the dislike is probably mutual; bees' antipathy to particular individuals being as remarkable as their liking for others, and, whilst some persons may handle them with impunity, there are others who dare not venture within yards of their hives without being attacked. That the odour of some persons, not perhaps in itself unpleasant, may yet be disliked by the bees, is the most reasonable explanation of the strange facts that can be offered.

Swalcliffe, Banbury, Oxon.

IN

ARTISTIC GEOLOGY.

FFESTINIOG AND ITS NEIGHBOURHOOD.

By T. MELLARD READE, F.G.S., &c.

N addition to its reputation for picturesque scenery, and the soft beauties of its vale, Ffestiniog is a very good centre for the geological student. Situated on a sort of promontory between two valleys, the Cynfael and the Dwyryd, at a sufficient elevation to maintain a bracing atmosphere, the mind and body retain that elasticity which makes mountain scenery so enjoyable. At the same time, those whose delight is the investigation of nature can fully gratify their cravings. I will proceed to describe some of the geological problems which force themselves upon the notice of the thoughtful mind.

SURFACE FEATURES.

The grand flank of Moelwyn, perhaps the finest mountain of its height I have ever seen, is to my mind of more interest than the much, if not over, praised vale. It can be seen at one view from base

to summit. The river Dwyryd runs deep below you at the bottom of the vale, while Moelwyn rises from a tree-covered breastwork of hills in a great and serried scarp from Tan-y-Bwlch to Blaenau Ffestiniog slate quarries. Its beauty, to my mind, is its variety, the contrast between the ornamental nature of its foreground of hills, and the steep treeless scarp of its main mass. Facing the south-east, it changes much under the varying light of the sun, now lighted up in every detail of its structure, and anon a vast mystery of gloom. A descent from the village of Ffestiniog to the Dwyryd down a steep footwalk gives us some very picturesque views. The vale is well wooded. We cross the river by a foot-bridge, noticing, by the way, some well-rounded boulders in the river bed. Ascending the other bank we strike the main road which skirts a deep and picturesque ravine thickly timbered. Arriving at the turnpike, we turn towards Tan-y-Grisiau, noticing a large bank of drift which lies near the fork of two streams, one of which rises in Cwm Orthin, the other nearer the slate quarries of Blaenau. The road to Tan-y-Grisiau skirts the former stream, in which are two very picturesque falls. The lower fall is crossed by a bridge just above it. Passing over this, with some climbing through ferns and heath, and over walls. ascending the right bank of the stream, we get a very beautiful view of this upper fall. The rock here is part of a large mass of intrusive Syenite forming Moel Tan-y-Grisiau, and the stream has cut back a deep gorge into it. Further along, the stream can be again crossed by another bridge near to Tan-y-Grisiau. At the Tan-y-Grisiau station of the narrow gauge or "Toy" railway we begin the ascent of Moelwyn. Skirting the railway and ascending a footpath, not very difficult climbing, we reach Llyn Trwstyllon, a cwm lying under the great scarped face of Moelwyn. The rocks at the open part of the cwm slope towards the lake. The dip is 18° north-west. It appears to be striated south-east, but very faintly. The surface of the rock is much broken up in places since the glaciation. The cwm is a very perfect cup, broken through on the south-east side. The scenery is very fine. A steep ascent of green turf-covered slope brings us on to the back of Moelwyn. The remainder of the ascent is up what appears from below a small hillock, but develops into a mountain when you get on to it. It is very steep and grass-covered, sheep grazing up to the very top. A magnificent view rewarded our exertions, the weather being delightfully bright and clear, and the light breeze exhilarating. I have been up many mountains, but never saw a finer view than that to the north-west over Snowdon. I preserved my impressions in a sketch taken at the time, in which the mountain forms are reproduced in outline. It represents a grand series of mountains rising in a low but sublime pyramidal mass culminating in the peak of Snowdon. The hollow of Llyn Llydaw, the entrance to the pass of Llanberis, and the Glyders, and other

well-known features are distinctly visible. To the left is a glimpse of the sea high up in the horizon. Moel Hebog, the Glaslyn and pont Aberglaslyn are also distinguishable. The Glaslyn runs like a silver streak through a mass of green fields to the Traeth Mawr. Beyond is the embankment across the marsh for the road and railway terminating in Port Madoc, the houses showing distinct and clear with Moel-ygeist in the back-ground, and in the far distance stretches the long promontory of Caernarvonshire till almost lost in the blue haze of the distant sea. The Rivals showed like little cobs on the relief map of Caernarvonshire. Further to the west shone the brilliant orange sands of the estuary of the Dwyryd below Tan-y-Bwlch, and beyond this was the sea with its shore sweeping round to Harlech Castle, which, with its towers, appeared as a little group of dots. To the south could be seen the Rhinogs, and the long scarped face of Cader Idris beyond, and, to the east, appeared a sea of mountains out of which arose the Arenigs and the Arrans. To the north the land rose and fell in billowy sweils till lost in the grey haze.

The immediate foreground of the view over Snowdonia is occupied with the remarkable mountain called Cynicht. From the road between Tan-y-Bwlch and Bethgelert this mountain looks like a pyramid; but it is there seen in profile. From the summit of Moelwyn we see it as a long ridge with its flanks scored with gullies and talus, which traverse its steep sides like streams till they become confluent in the talus cones at the foot. Immediately below, to the left, were the rocky north-west precipices of Moelwyn. The day was a perfect day, the clouds floating high, the air clear and exhilarating, yet warm.

I have dwelt upon this view perhaps more than a geological article warrants; but let us pause and consider if it will yield us any scientific information.

The traveller about Ffestiniog will soon find out, if he carries a compass with him, that the general strike of the rocks is from south-west to north-east. At right angles to this the strata have been thrown into a series of anticlinal and synclinal folds, broken up, and, to some extent, obscured, by faults, it is true. Perhaps this feature in the structure of the country can be best appreciated in the general view of the mountains of Snowdonia obtained on the coast road between Maentwrog and Harlech. It can, however, be observed on Moelwyn itself. A slate quarry on the back of Moelwyn shows the rock to dip rapidly to the north-west. Without going into details, the structure of the mountain is a series of shales and slates, with an interbedded massive series of felstones and felspathic ashes.

It is these hard massive beds which form the grand scarp in which lies Llyn Trwstyllon. The whole of these beds belong to the Lower Silurian series, commencing with the Lingula beds in the Ffestiniog and Tan-y-Bwlch valley, and terminating in the Bala beds at the summit of Cynicht. The slates of

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commerce are interbedded in the series, and as the beds dip steeply to the north-west the quarrying operations have to be mostly followed by galleries, and not in great cuttings open to broad daylight, as is the case with the quarries at Penrhyn, near Bangor, which lie in the older Cambrian slates. To the north, in the valley of Dolwyddelan, the calcareous ashes there largely developed are the actual representatives of the Bala limestone and the Caradoc sandstone of Shropshire, and the vast masses of ashes that crown the felstones of Snowdon and Moel Hebog are but an enlarged development of the same strata.*

To understand the present surface form of the country, it is requisite to keep in mind the great fact that the whole of the Upper Silurian strata which formerly covered Merioneth and Caernarvonshire has been entirely removed by denudation. It is only when we get as far to the south-east as the river Vyrnwy, where the great reservoir to supply Liverpool is being constructed, that we come upon the remains of the Upper Silurian, here preserved in a synclinal. A general glance at the geological map of North Wales shows the persistent strike of all the rocks from south-west to north-east. It is along these lines that the denudation has principally acted, many of the main valleys possessing the same parallelism of direction. The hard beds of felstone and ash, and the intrusive greenstones and other igneous rocks, have helped to preserve that peaked and ridgy character which here gives the distinguishing beauty to the scenery.

A walk down the north-west slope of Moelwyn brings us to Bwlch Cwm Orthin, a pass between Cwm Orthin and Cwm Croesor, which lies between Cynicht and Moelwyn. Here we may stop to examine some slate works. The slates are generally of small size, but beautifully true and fine. Descending the path to Cwm Orthin, we get a good view of the Llyn below, now being rapidly filled up with the debris from the Cwm Orthin slate quarries.

At the entrance to the cwm may be seen those well-rounded rocks specially noted by Ramsay as good instances of roche moutonnée glaciation. Beyond these we may again examine slate works. Here some of the slate is of that peculiarly fine and soft nature which fits it for manufacture into school slates, the process of which may be watched. I impressed on my mind the view of Cwm Orthin looking towards the glaciated rocks, in the best possible way, by sketching it. It is a true rock basin, the dip of the strata to the north-west and the hardness of the felspathic rocks at the outlet, no doubt being determining causes, together with ice, in producing this form of denudation. A steep down-hill walk brings us to Tan-y-Grisiau station, but we may pause a moment to look at the waterfall. The stream from

*Ramsay, "Memoir of the Geology of North Wales," Ist ed. p. 95.

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