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 INSECTS occurrence in situations apparently far away from any colony of the wild bees at whose expense it has passed its early stages, is not easily accounted for. Turning now to the water-beetles, we shall find the whirligig beetles {Gyrinida) conspicuous by reason of their numbers, and interesting on account of their structure. These insects are known to all from their habit of floating lightly on the surface of the water, and performing graceful complex curves round one another, apparently without colliding. They are admirably constructed for a mode of life which is comparatively rare in the insect world. They have four eyes, one pair on the upper surface and another on the lower, and very short antennas which can be packed away in the space between the upper and lower pairs of eyes on each side of the head. They are able to dive to escape danger, and then carry with them a small supply of air under the wing-cases, from which a portion of it protrudes as a bright silvery bubble, but they do not stay long beneath the surface. When handled they exude a milky-white fluid which has a very disagreeable smell. Their two hind pairs of legs are beautifully modified so as to serve as paddles, expanding when moved in a backward direction and collapsing into an extremely small space directly the resistance they meet with is in the other direction. The construction of their fore feet is very peculiar. In other water-beetles the soles of the fore feet are directed downwards, but in the whirligigs the fore legs are so set on that the soles of the fore feet are not turned downwards, but towards one another, and the assemblage of suckers which constitutes the prehensile apparatus proper to the soles of the fore feet in the males of water-beetles is in these carried on what is really the side of the fore foot and not the sole. As might be expected from its physical features, Norfolk is especially rich in Gyrinidce^ nine out of the eleven kinds known as British having already been found there. Some of the species congre- gate in immense numbers in the open water near the banks of rivers, whilst others perform their gyrations in the shelter of the stems of water- plants, and are rarely seen except by entomologists in search of them. In some kinds, as Gyrinus elongatus^ found in ditches near the coast, and G. bicolor, a denizen of Hickling Broad, a small percentage of in- dividuals are of a diff^erent form to the others, being quite parallel-sided ; whether this abnormal form is of advantage or otherwise to the in- dividual does not appear. In the following list the names of the captors or recorders of species when other than the author are given after each entry. The ento- mologists referred to are : C. C. Babington, F.R.S., Professor of Botany at the University of Cambridge ; T. Hudson Beare, F.E.S. ; Alfred Beaumont, F.E.S. ; E. C. Bedwell, F.E.S. ; W. G. Blatch, F.E.S. (ob. 1900) ; J. B. Bridgman, F.L.S., F.E.S. (ob. 1899) ; Thos. Brightwell, F.L.S., formerly of Norwich ; the Rev. J. Landy Browne of Norwich ; the Rev. John Burrell, A.M., F.L.S., F.E.S., Rector of Letheringsett (ob. 1825) ; E. A. Butler, F.E.S,, ; G. C. Champion, F.Z.S., F.E.S. ; the late Rev. Hamlet Clark ; the late G. R. Crotch ; the Rev. C. T. I 113 I