Page:VCH Cornwall 1.djvu/221

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INSECTS The house cricket (Gryllus domesticus) is fairly common still in bakehouses and old kitchens throughout the county, but is not nearly so plentiful as it was twenty years ago. The mole cricket (Gryllotalpa gryllotalpa) was first recorded from Cornwall by Stephens. It is still found in the county, and one warm spring evening two years ago the writer was delighted to hear the welcome ' churr ' of this fine insect only a short distance away from Truro. During the last six years seven specimens have been captured in the county and many more could have been taken but for the fear of exterminating it. The Gryllopalpa cophta of de Haan, merely a variety with abbreviated wings, was captured last year (1905) at Marazion. NEUROPTERA Psocids, Stone-flies, Dragon-flies, and Lace-wings With the exception of the Dragon-flies, the Neuroptera of Cornwall have received very little attention. Some notes by Mr. W. C. Boyd on his captures in the west of the county in vols. xxxviii and xxxix of the Entomologist' t Monthly Magazine are apparently the only published records of any extent. The list that follows is based on the work of the writer and his biological pupils from 1900 to 1904, on a small collection formed by the late Mr. W. E. Baily of Penzance, and on data published or furnished by fellow entomologists. It contains 24 Dragon-flies, 66 Pseudo-neuroptera, 34 Neuroptera-Planipennia, and 98 Trichoptera, in all 222 species, and is undoubtedly very incom- plete. The arrangement followed in the Dragon-flies is that of Lucas, in the Trichoptera that of McLachlan in his European Trichoptera, and in the remainder that of McLachlan and Eaton in their Catalogue of British Neuroptera. The author's thanks are due to Mr. W. J. Lucas for much kind assistance. He also wishes to express his great obligation to the late Mr. R. McLachlan, without whose help the article could not have been undertaken. ODONATA Dragon-flies In spite of their evil reputation as suggested by the popular names of ' Horse-stangs ' and ' Blood-suckers,' dragon-flies do not possess even the rudiments of a sting, and their jaws are incapable of making any impression on the human skin. Their large size, truculent appearance, and uncanny flight are no doubt responsible for the remarkable prejudice that has everywhere caused them to become objects of dread. It is true they are carnivorous in their habits and possess an almost insatiable appetite for insects, which by their superior power and agility of flight they capture on the wing, but this persistent hawking of insect life is, from an economical point of view, beneficial rather than otherwise, and their ferocity is exhibited only in the facility of capture and promptness of consumption of their prey. The dragon-flies in Cornwall, as in many other counties, have been unaccountably neglected by resident entomologists. Dr. Cocks paid some attention to them (see Royal Cornwall Polytechnic Society's Report for 1862), but the only recent attempt at enumeration is a paper by the late Mr. W. E. Baily, entitled ' Our Common Dragon-flies,' in vol. ii (new series) of the Transactions of the Penzance Natural History and Antiquarian Society. Several additional records have been published by Major A. Ficklin and others, and these, with the captures made by the students during the past three years, bring the total for the county up to twenty-four. The handsome Sympetrum striolatum is widely distributed over the county, occurring even on Tresco and St. Mary's, Isles of Scilly, and at least occasionally on Tean. In many localities it is abundant, as in the neighbourhood of Truro, Falmouth, and Penzance, in the valley of the Gannel, and here and there on the Camel. It has been taken every month from June to December, but in cold weather becomes so sluggish that it can be caught with the fingers. Sympetrum scoticum was first taken near Falmouth in July, 1902. Since that date it has been captured on six occasions in the same locality and, with the exception of a wandering male, all within seventy yards from the spot where the first specimen was obtained. A single specimen has also been reported from the Tamar above Launceston. A female of Sympetrum fonscolombii, presumably the second captured in the British Isles, was taken by W. C. Boyd on 4 June, 1903, at a little village called Sheffield on the road to Trewoofe, near Penzance (E. M.M. vol. xxxix, 201). Libellula depressa is generally distributed over the whole county, and is frequently found at a considerable distance from water. In spite of its wide range it does not seem to be plentiful any- where, and on account of its wariness is much more frequently seen than caught. Libellula quadrimaculata is widely distributed but evidently local, and in most years nowhere common. On 20 June, 1901, however, fourteen examples were taken and many more seen near I 169 22