122 



HARDWICKE'S SCIENCE-GOSSIP. 



colour, of delicate intermingled pinks and yellows 

 with the embryo curved, like an annulus round the 

 circumference of a central store of farinaceous albu- 

 men ; the object well displays the hilum, or scar of 

 union with the mother plant. 



The integuments of seeds are composed of structu- 

 ral membranes of significant interest ; after soaking, 

 and in some cases boiling, they may be teased out, 

 and excellent preparations secured ; the disclosure 

 of spiral tissue in the testa of the seeds of Cobcea, 

 and Collomia, an oft-repeated demonstration, still 

 retains its old interest ; a thin particle cut from the 

 surface, placed in a drop of water, between glasses, 

 will disclose positive action ; cells bursting, and 

 imprisoned coils darting forth in all directions. 



Of seeds, in their simple and natural integrity, as 

 objects of beauty, may be mentioned : poppy and 

 mignonette, showing reticulations ; Eccremocarpus 

 scaler, with membranous wings ; this seed mounted 

 in balsam is a fine polariscope object. Antirrhinum 

 majus (snap-dragon) roughly corrugated ; the seeds 

 of the carrot have curious radiating processes ; those 

 of wild indigenous plants are always attractive, and 

 exhibit marked peculiarities ; Goose-grass, covered 

 with equidistant hooks ; Burr-reed with four ribs 

 running longitudinally, terminating in projections, 

 each armed with a double row of barbs ; even chick- 

 weed has a spinous seed, worth looking at. As 

 regards configuration the most striking are the 

 reniform, and the obovate, as in the larkspur, 

 marked with prominent irregular ridges. 



The following carefully selected list of microscopic 

 seeds, as showing peculiarities in great variety, is 

 extracted from the " Micrographical Dictionary'' 

 (Van Voorst). 



Hypericum, Lychnis, Stellaria, Reseda, Lepidium, 

 Nigella, Erica, Anagallis, Orobanche, Linaria, 

 Chironia, Gentiana, Datura, Nicotiana, Petunia, 

 Sedum, Saxifraga, Capparis, Elatine, Gesnera, 

 Begonia, Delphinium, Scrophularia, Antirrhinum, 

 Maurandya, Sphenogyna, Hyoscyamus, Semper- 

 vivum, Silene, Dianthus, Papaver, Digitalis. 



Seeds perfectly dry and clean, require little or no 

 preparation, as opaque objects ; the beauty of many, 

 as Drosera, Hydrangea, Pyrola, Orchis, and very 

 minute specimens, is much enhanced by mounting in 

 balsam in a cell, after a washing in spirit of turpen- 

 tine, in this -way, the edges or any projecting parts, 

 as hairs, spines, corrugations, hooks, &c, are within 

 reach of the dark ground illumination, which added 

 to condensed light from above, brings out their 

 perfect beauty, with binocular vision, presenting a 

 solidity eminently adapting them for artistic study 

 and practice as models of form, colour, and shadow. 



Crouch End. 



A new volcano is said to have been discovered in or 

 near the government of Smolensk in Russia, and to 

 have been showing signs of activity. 



ARTISTIC GEOLOGY. 



Ffestiniog and its Neighbourhood. 



By T. Mellard Reade, F.G.S., &c. 



[Continued from p. 113.] 



JT) WLCH Drzus Ardudwy. — We may devote a 

 -L-) good long day to this excursion, which will, with 

 fine weather, well repay the geological student no less 

 than the lover of scenery. Taking an early train to 

 Trawsfynydd on the railway to Bala, we get on to the 

 main road from Maentwrog to Dolgelly. About two 

 miles frcm the station, and about half-a-mile before 

 turning off to the right, on the east side of the road, 

 is an outcrop of the Cambrian rocks, here of a blue 

 slaty nature, the direction of dip being from west to east, 

 which it will be well to bear in mind. Turning off 

 along an unfrequented road, we cross the Afon Eden 

 by a foot bridge, and about a mile onwards we cross 

 an extensive surface of bare rock having a dip about 

 nine degrees north-west ; but it varies, as the surface 

 is part of an anticlinal curve. No glacial strice are 

 to be seen, but the smoothness of the rock may never- 

 theless be due to glacial action. 



It may be as well here to observe that we have 

 been walking along, and then across a valley denuded 

 out of an anticlinal and situated at a very considerable 

 altitude, as any one who walks from Maentwrog will 

 find out before he gets to Trawsfynydd. This valley 

 is a wide trough, running north and south, occupied 

 entirely by Cambrian rocks, out of which, indeed, it 

 has been scooped. 



The eastern side is for a considerable distance 

 bounded by a fault which must pass very near to 

 Trawsfynydd station, though I did not see it. This 

 elevated valley is remarkable, inasmuch as it is 

 divided into two watersheds, the southern part being 

 drained by the Afon Eden towards Dolgelly into the 

 Mawddach, and the northern by the Afon Pryser, 

 which rises in the Silurians to the east, and flows, 

 after passing round the village of Trawsfynydd to the 

 estuary below Maentwrog, discharging over the 

 beautiful falls of the Rhiadr Ddu before alluded to. 



From the smoothed rocks we left off at to describe 

 the valley, there is a gradual ascent to the Drws 

 Ardudwy, which is a wild pass between Rhinog 

 Mawr and Rhinog Fach, two grand Cambrian 

 mountains. As we traverse the pass, or the " gates " 

 of the Ardudwy, we are going in a south-westerly 

 direction. From the time of entrance between the 

 Rhinogs to the summit of the pass, we are still 

 rapidly ascending. Beyond the summit we may rest 

 to survey the prospect, taking care to have a good big 

 block of stone behind us, for the wind blows keenly 

 through this mountain channel. Looking back, that 

 is to the north-east, we have a sublime view of the bare 

 and somewhat terraced flank of Rhinog Fawr. The 

 grandeur of the scene is due to the enormous mass of 

 rock which is almost devoid of vegetation, and the 



