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mountain was enveloped in a shower of sleet, from which it might be inferred that the continual fiow of electricity from the ground towards the clouds helped in a great degree to their formation. Thus, during the observation of the 22nd of June, 1865, in particular, all the rocky points were under the same meteorological conditions, while the valleys situated between the points received violent showers of rain.
“However we must take into account the higher temperature of the hollows, where sleet about to fall turns into rain. M. de Charpentier long ago pointed out the importance of this fact, and with sleet or snow, the results must be the same.
“ELECTRICITY OF THE JURA. “ 5. Electricity of meadows near Courtavon.
“An instance of meadow lightning has been observed in the neighbourhood of Porentury, at the foot of the Jura and near Courtavon. About 100 mètres above the valley, stands the ancient castle of Morimont, the restoration of which has been entrusted to the Engineer of the mines, Quiquerez de Délémont, a man well-known by his splendid mining and archæological works. Being engaged with directing his workmen, on the 26th of August, 1865, he was overtaken by two successive storms between nine and twelve o'clock. At three o'clock in the afternoon there was a third, when the clouds were very low down. Electricity was then exhibited in a frightful manner over the whole extent of the adjacent meadows; sparks succeeded each other in rapid luminous trains passing over the grass instead of through the air. The general noise was such that the individual cracklings were not distinguished. It did not rain; but the observers were almost in the clouds and were all drenched with the morning showers.
“During this journey, three or four leagues east of Morimont and on the continuation of the Jura chain, but a few minutes later, lightning was remarked which ran over the fields and meadows, as if the earth was all on fire. Thus M. Quiquerez was not the only one who observed this phenomenon, and I may add that the storms extended to Lyons.
“6. Electricity of the lakes near Neufchâtel.
"Discharges of the same kind are manifested on lakes, and M. Arago has already noticed the fact in a pond at Parthenay (Vendée) in his Notice sur le tonnere, page 371.
“The Swiss Société d'Histoire saw an example, on the 2nd of August, 1850, while sailing on the lake of Moret about eight or nine o'clock at night. They then heard thunder at Montbéliard, Châlon, and Bourg.
“ Also on the lake of Bienne, the boatmen of Nidau thought on one occasion that they were crossing a sheet of fire."
NOTES ON THE CRUSTACEAN FAUNA OF THE
(With a Plate.) Having, during several short rambles amongst the mountains of Cumberland and Westmoreland, paid considerable attention to the microscopic Crustacea which inhabit the numerous lakes and tarns of that district, I propose, in the following pages, to offer a few remarks relative chiefly to the distribution and habitat of the various species, and also to describe briefly two or three new or little-known forms. And though I take the group known as the English lakes, par excellence, for the groundwork of my remarks, I shall also include therein to some extent the lakes of Northumberland, Dumfriesshire, Selkirkshire, and Kirkcudbrightshire, amongst which I have spent many pleasant days with net and collecting bottles. The lakes included in this programme may indeed be looked upon as forming in themselves a pretty well-defined group intermediate between those of the Scottish Highlands on the one hand, and of the Southern English Lowlands on the other. Whether the Crustacea of the more northern Scottish waters differ materially from those of the south cannot now be stated, as they have yet received scarcely any attention ; but from all that we know of the lacustrine Crustacea of the English Lowlands, it may confidently be asserted that the difference is here very great indeed.
And it may be interesting to tourists with a love for natural history (but who begin to find the geology, botany, and mineralogy of our islands worn somewhat threadbare, so far as the discovery of new things is concerned) to know that the microscopic Crustacea of our ponds and lakes, and especially of mountain lakes, are sure to afford novelties to the diligent observer for many a year to come. Not that the discovery of new species ought to be the chief ambition of the naturalist, nor that even this may not yet be done by the hard-working botanist or geologist; but there is, nevertheless, a legitimate pleasure in discovering and describing forms of life which have been hitherto unknown; and in no branch of investigation are we, perhaps, more likely to find it, than in that of which we are here treating.
The higher groups of Crustacea (Amphipoda and Isopoda), which are abundantly represented in lowland ponds and streams by such creatures as Gammarus pulex and Asellus aquaticus-animals of the sandhopper and woodlouse typeare scarcely to be found in mountain lakes, though we occs. sionally meet with them in very small bog-pools on the hill