Campbell), 1250 feet above sea level. Common in a small pool in the little islet, the site of the vitrified fort in the Kyles of Bute; no other Ostracod being found in the same gathering. This pool is only a few feet above high-water mark, and a few yards in diameter, and must be subject to a considerable amount of spray. Also in great abundance in a newly dried-up pool, a little above high-water, on Hunterston shore, Ayrshire, on the damp mud, under a thick coat of dry moss. The only other species found with it were two examples of Candona candida, and three of Cypridopsis aculeata. CANDONA SIMILIS, Baird. Candona similis, Baird. Brit. Entom., p. 162, pl. 19, figs. 2-2a. Brady and Robertson, Ann. and Mag. Nat. Hist., ser. iv., vol. vi., p. 52, pl. 1, fig. 62. Has been more generally met with in lochs than in smaller patches of water. Moderately common in Woodend and Lochend Lochs, near Glasgow, and in Burnbath Loch and Houston Dam, Bridge of Weir. Common in Duddingston Loch, Edinburgh. CANDONA NITENS, sp. nov. Found in Mugdock Loch, near Milngavie, moderately rare. Oct. 1st. Johnstone Loch, moderately common. June 3rd. Crosslee, moderately common. May 17th. Bishop Loch, moderately common. May 30th. Pilmuir Dam, Burnside Loch, Govan Colliery Dam, Hairlaw Loch-common. CANDONA KINGSLEII, Brady and Robertson. Candona Kingsleii, Brady and Robertson, Ann. and Mag. Nat. Hist., ser. iv., vol. vi., p. 17., pl. ix., figs. 9-12. Not unfrequently in both deep and shallow water. In Lochlomond in 12 to 20 fathoms. Baron Loch, Peebleshire; Frankfield Loch; Eaglesham Dam; Long Loch (J. Smith). Common in both Skye and Lewis. Lochearnhead (P. Cameron). CANDONA DIAPHANA, Brady and Robertson. Candona diaphana, Brady and Robertson. Ann. and Mag. Nat. Hist., ser. iv., vol. vi., p. 18, plate v., figs. 1-3. In Hairmyres and Lambriden old limestone quarries, moderately common; Mugdock Loch, near Milngavie; brackish pond, Millport. CANDONA HYALINA, Brady and Robertson. Candona hyalina, Brady and Robertson. Ann. and Mag. Nat. Hist., ser. iv., p. 18, pl. ix., figs. 5-8; plate v., figs. 4-11. In Frankfield Loch, St. German Loch, and Little Loch; Craigton Dam, and Possil Marsh; Hairmyres old limestone quarry, Dumfries. DARWINELLA STEVENSONI, Brady and Robertson. Polycheles Stevensoni, Brady and Robertson. Ann. and Mag. Nat. Hist., vol. Darwinella Entom., p. 141, pl. ii., figs. 13-17. Mon. Post-ter. At Loch Broomhill, Dumfriesshire, the only Scotch locality yet recorded. LIMNICYTHERE INOPINATA, Baird. Cythere inopinata, Baird. Brit. Entom., p. 172, pl. xx., figs. 1, la-e. p. 173, pl. x., figs. 8-11. Mon. Post-ter. Entom., Not unfrequently found amongst the mud in lochs, ponds, and canals. In Duddingston and Lochend Lochs, Edinburgh, St. German and Mugdock Lochs near Glasgow, Glasgow and Paisley Canal, moderately common. The species is not rare, although not generally met with in consequence of being chiefly confined to the mud. LIMNICYTHERE SANCTI-PATRICII. Limnicythere Sancti-Patricii, Brady and Robertson, Ann. and Mag. Nat. Hist., ser. iv., vol. iii., p. 17, pl.xviii., figs.8-11; and pl. xxi., fig. 4. In Loch Libo, rare; in a ditch at the side of Bishop Loch but not communicating with it. CYTHERIDEA LACUSTRIS, G. O. Sars. Cythere lacustris, G. O. Sars. Zool. Reise i Sommeren, 1863, p. 30. Cyprideis torosa, Jones (in part). Ter. Entom., p. 21, pl. ii., figs. la-ld; and woodcut, p. 16, fig. 2. Cytheridea lacustris, Brady. Mon. Rec. Brit. Ost., p. 427, pl. xxvi., figs. 18-21; and pl. xl., fig. 2. Not uncommon in Glasgow and Paisley Canal, west of Pollokshields, and sparingly in the Clyde, near Langbank. This species is rather sluggish, mostly stationary on the mud, or partly embedded in it, with the valves partially open, apparently satisfying itself with what the movement of the water may bring in its way. Candona torosa, Jones. CYTHERIDEA TOROSA, Jones. Ann. and Mag. Nat. Hist., ser. ii., vol. vi., p. 27, pl. iii., fig. 6. Cyprideis torosa, Jones. Mon. Ter. Ent., p. 21, pl. ii., figs. la-li.; and woodcut, fig. 2, p. 16. Cytheridea torosa, Brady and Robertson. Ann. and Mag. Nat. Hist., ser. iv., vol. vi., p. 21, pl. viii., figs. 6-7. Brady, Crosskey, and Robertson. Mon. Post-ter. Entom., p. 178, pl. xv., figs. 11-12. Var. teres, pl. vii., figs. 1-2. In great abundance on In brackish water, chiefly estuarine. the banks of the Garnock on Misk Farm, near Kilwinning, in small holes, a few feet wide, formed in the turf, the bottom being soft mud covered by a few inches of water, and overflowed by high tides. The margins of those pools are excavated for many inches all round. Small eels, from three to four inches long, are common in the bottom mud. Var. teres.-Generally in company with the above. The following remarks may help beginners, who generally work at great disadvantage and loss of time from not knowing properly when or how to collect, or how to preserve what they may have collected. The latter is perhaps the greatest source of discouragement to many, who find, after a few years' enthusiastic labour, that they have only accumulated a vast amount of ill-arranged and often cumbersome material, neither pleasant to look upon nor useful to consult. In this, as in all other branches of Natural History, it is absolutely necessary (1) to have the locality affixed to every specimen intended for preservation. To do this is within the reach of every one who collects for himself. If it is neglected to be done at the time of collection, it may be impossible to do it with any certainty afterwards. (2) The next important point is to have the name attached to the specimen upon the first opportunity, and not left merely to memory, and it then becomes a useful assistant in other determinations. (3) Every specimen which it is desirable to keep should be carefully laid past and arranged with others in the most convenient way for reference. I shall indicate briefly (1) Where the Ostracoda are principally to be found. (2) What season of the year is most favourable for procuring them. (3) By what means they may best be secured. (4) How to preserve them most conveniently for inspection and reference. I. Places where to be found.-They are to be found in lakes, tarns, ponds, lagoons, canals, ditches, and often in very small patches of water, and in slow-running streams; but in the latter by no means commonly, except in weedy recesses protected from the currents, or where clumps of thickly-growing plants abound. Nowhere, throughout Scotland, is there any want of such places either in number or variety, whether we regard the depth of water, varying from the thinnest covering to the deepest lakes, or their situations, ranging from the sea level to high mountain tarns; or the character of the basin in which they lie, rock, peat, clay, &c.; or, lastly, the impregnated mineral contents. Ostracoda are generally more abundant in the smaller tarns or ponds, overgrown with weeds, than in deep and large sheets of water, where the surging of the waves is unfavourable to marginal vegetation; yet I often find, that places greatly overgrown with plants are not always the richest in Ostracoda, but sometimes the reverse-probably in such cases by affording more suitable conditions to a greater host of enemies. Ostracoda are occasionally obtained in small tarns and ponds where the water has been nearly dried up, leaving only a little at some central depression; and even in the damp mud, whence the water has disappeared, good gatherings are met with, as well as in the scanty water of furrows in old pasture land, and which are dry during the greater part of the summer. It is indeed surprising, as regards many of these patches of water, how speedily after rain they are found swarming with Ostracoda and other Microzoa. In some instances it has been observed that, after the rains certain species are absent which had been present before the ponds dried up, while by next season they again become abundant. Whatever means of distribution there may be, it is very probable that this renewed life proceeds in a great measure from ova. That the ova retain vitality for a long time is certain. The late Dr. Baird, of the British Museum, showed Dr. G. S. Brady and myself a jar containing numerous forms of animal life which had made their appearance from mud taken from a dried-up canal in India during the hot season, and kept in the dry state for a considerable time after reaching this country before being subjected to water. Shortly after water was supplied, many living forms made their appearance. Where the pools are small and subject to be dried up during summer they seldom contain many species, although in such cases one species may prevail greatly. Limestone districts are favourable to Ostracoda, but all rock or clay surfaces are better than peat. Where there is nothing but pure peat, or peaty ponds fringed with Sphagnum, few or no Ostracoda may be expected. They are seldom searched for successfully where the lakes or pools have risen much by heavy rain-falls, nor in mill-dams, where the water is drained off rapidly, leaving broad, bare margins. It is otherwise where the water in the pools is decreasing gradually by evaporation. Then these animals appear to have time to follow the water, and may be taken abundantly when thus brought closer together in the small shallow pools left here and there. Moorland roadside ditches are more promising than those at some distance from the road. This may arise from a supply of material from the drainage of the road, which may be requisite to build up the shells of these minute crustaceans. Ostracoda are seldom absent in ditches or marshes which contain a little ochreous deposit with a metallic bluish scum on the surface of the water; they are more common in broad shallow ditches than in those more narrow and deep, and are rarely met with in springs or in ponds abounding with fish. Neither do they thrive where amphipods prevail. These little bivalve crustaceans are not always fastidious in their choice of habitat, sometimes disporting in pure fresh water, at other times revelling in water of very questionable character, while others affect brackish water, although they live in very different degrees of the saline element. The Govan Colliery Dam, which is close to the terminus of a railway, is subjected to the dust from loading and unloading of the waggons, and to the deleterious fumes of a range of brick kilns |