HARDWICKE'S SCIENCE-GOSSIP. 



l2 7 



seen in the valley below me on my way up, which 

 here has its source, and for the first part of its pro- 

 gress now runs underground. So far as I could make 

 out, its original course from the lake had become 

 choked up with large stones and boulders, and its 

 progress having thus been stopped, the water had 

 gradually wormed its way into the soft ground under- 

 neath them, resulting in its at present running in a 

 subterraneous passage. 



After a very steep ascent from the lake, I reached 

 a fairly flat piece of ground, gently rising towards the 

 top of "Drum," and here I entered the first tract of 

 heather, mixed with whin and other plants, I had so 

 far met with during the day. I wished the weather 

 had been more favourable, for the ground looked 

 very promising for insect hunting, and at a height of 

 over 2000 feet there was no knowing what interesting 

 things one might have come across. As it was, I had 

 not gone far, carefully scrutinising the herbage within 

 "ken" on either side, before I espied a Geometer, 

 settled with closed wings on a tuft of heather, which 

 on inspection proved to be a remarkably richly- 

 marked and dark-banded specimen of Cidaria popn- 

 lata. I was particularly pleased with the marking of 

 my capture, which was just what I had expected, or 

 rather hoped to meet with, in any species I should 

 be lucky enough to take at such an altitude ; for 

 these Alpine forms differ from their lowland represen- 

 tatives, seeming, as I imagine, several generations (or 

 scores or hundreds of generations) behind them in 

 development, and therefore exhibiting more traces 

 of the original type ; as in this instance, the dark- 

 banded variety I had just picked up pointed much 

 more distinctly to the earliest form of a Lepidopterous 

 insect, generally considered as one with several dark 

 bands traversing the wings from costal margin back- 

 wards, than its ordinary type taken in lowland 

 regions, which is certainly evolved many generations 

 further. In confirmation of this, it is an interesting 

 fact to note that this specimen was taken quite fresh out 

 on September 5th, whereas the usual time of appear- 

 ance of the species in the lowlands is July, so that I 

 much doubt whether reproduction in this case could 

 be effected in the twelve months ; and supposing a 

 year was missed every now and then, it would, in the 

 course of ages, add up to a considerable sum, and its 

 lowland compeer would meanwhile leave it far behind 

 in gradual evolution. As a proof that the reproduc- 

 tion of a species frequently takes two years in high 

 altitudes, where it only takes one elsewhere, I may 

 mention that a little further on I picked up several 

 larva; of B. Rubi, the Fox Moth, which were almost 

 full grown, and so must have come from ova de- 

 posited the previous year, and they would certainly 

 never arrive at their perfect state this autumn, now 

 so far advanced. 



After the capture of this, to me, most interesting 

 specimen, I set to work to search for more, and was 

 rewarded by finding two others marked in a similar 



manner, and in equally fine condition. These were 

 the only insects I met with ; but, doubtless, the fact 

 of the fog coming on rather thick again, prevented 

 my making any further " finds." 



The gathering mists now began to become rather 

 more than pleasant, and made it very difficult to be 

 quite sure of the direction in which one was going. I 

 at once brought out my compass, and steered up the 

 hill, as I thought straight for the summit of " Drum," 

 2527 feet, which, according to the ordnance map, was 

 marked with a heap of stones ; but I was quite unable 

 to find it, though I got upon what seemed to be the 

 highest ground about. However, after wandering up 

 and down for some little time, I gave it up, and also 

 abandoned Llyn Dulyn as well, and I pressed on by 

 compass (for there was no seeing anything) towards 

 the east, which course I knew must take me over the 

 top of the watershed which divides the sea from the 

 Conway valley. Before long I began, as I expected, 

 to descend ; I had not gone far, however, when the 

 clouds commenced to lift, so I halted, for the chance 

 of their still clearing sufficiently for me to visit Llyn 

 Dulyn. After a short time the aspect of affairs 

 improved so much, that I made up my mind to try 

 my luck, and accordingly set off direct south along 

 the ridge I was then on, to traverse a distance 

 of about three miles, as far as I could make out by 

 the map, to the Llyn. 



The ground here was very boggy. It seems strange 

 that so much water should lie at the very top of a 

 mountain like this, where one would think all the 

 moisture should drain off its sloping sides ; however, 

 it certainly does not, and for about a mile I found 

 progress exceedingly precarious, for the ground was 

 very " shaky " indeed, and all around were deep 

 peaty holes, full of exceedingly black-looking water. 

 Many of them were far deeper than I could reach, or 

 their bottoms were covered with a kind of impalpable 

 peaty mud, in which one could poke a stick down, 

 down, down, as if the whole of the mountain was soft 

 pulp inside, and the turf one walked upon only a thin 

 " pie crust " on the top. Every now and then I passed 

 hollow places, where the said pie crust seemed to have 

 fallen in ; but holes of this nature, though large and 

 deep, were generally dry, and even stony at the 

 bottom, showing that the bog did not extend very 

 far down after all. 



About this time the mists to the south-west 

 suddenly divided for a few moments, and a ray of 

 sunlight burst upon the distant scene, revealing such 

 a chaos of rolling clouds and mountain peaks as to 

 baffle description ; but it was only for a moment, 

 and before I had time really to take in the view, and 

 try to identify on my map any of the hills I saw, they 

 closed again, and all was gloom and darkness as 

 before. 



On reaching firmer ground I crossed another ridge, 

 bringing me to the edge of a fine valley. Consulting 

 my map again, I found that far up at its southern end 



