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 A HISTORY OF CORNWALL Marazion, a locality where it does not seem to have occurred before or since. It is a well-known migratory species, and these may have been recently-arrived aliens from the Continent. Orthetrum coerulescens is apparently local. It is often common in the Land's End and Penzance district from July to October, is not infrequently captured in College and Trefusis Woods, Fal- mouth, and in the neighbourhood of Bodmin. It was recorded by Briggs from Bude, and in 1905 was plentiful about a little marsh adjoining a strip of wood in the Millook valley. That grand dragon-fly Cordulegaster annulatus is widely spread, and though somewhat local is often plentiful. It occurs on most of the streams on the east of the county, and on the Gannel, the Fowey, and Truro river. It has been taken by Briggs at Bude and beside the Camel above Wadebridge. At Falmouth it frequents College and occasionally Trefusis Woods, and Baily says that it is abundant everywhere around Penzance throughout the summer, even into late November. Brachytron pratense, though not common, is pretty generally distributed along the southern half of the county as far west as Falmouth. In the north it has been taken in the vale of Lanherne. Aeschna juncea is evidently scarce. One was taken by Marquand at Trevalyor, and one by Baily at Paul near Penzance, and the latter states that it has been seen at Marazion, Madron valley, and St. Ives ; C. W. Dale also records it from the Penzance district. One was obtained and several have been seen over the reed-beds at Pencalenick, near Truro. It is one of the most difficult insects in the county to capture. Aeschna cyanea is of frequent occurrence in the east along the middle and lower courses of the streams, and in the quieter country lanes. Along the south it is locally fairly common as far west as Mabe and Constantine. In the north it has been taken near Wadebridge. Aeschna grandis is rare, but has been taken several times on marshy land near Falmouth, once in the Technical School gardens at Truro, and once in the vale of Lanherne. The fairy-like Calopteryx virgo, with its gentle fluttering flight, is often one of the most attractive features of the wooded streams of the Penzance district during June, July and the early part of August. It is frequently seen near Falmouth, and is at times plentiful about Pencalenick and elsewhere in the neighbourhood of Truro. It is occasionally abundant by the Gannel near Trevemper Bridge, and is reported from the Camel above Wadebridge. It is common about Plymouth and locally so along the bush-fringed streams in the east of the county. Calopteryx splendens is much more local and not nearly so common as C. virgo. It is occasionally plentiful about Launceston, Egloskerry, and Altarnun, has been taken about Calstock and Botus-Fleming, and as far west as Truro river. Lestes sponsa was fairly common at Trebartha in August, 1902, but does not seem to have been recorded from any other part of the county. Platycnemis pennipes has been taken on the Inney near Lewannick, and has been reported from the Draynes river above Liskeard. Erythromma naias is not uncommon in the month of June on the moors and marshes of the Land's End and Penzance district. It has been obtained near Constantine, and is occasionally captured in the neighbourhood of Truro. Specimens have also been sent in from near Roche. Pyrrhosoma nymphula is widely distributed and on the whole common throughout the county. It is one of the earliest dragon-flies to appear, and on 26 April, 1901, was plentiful near Ruan Lanihorn. Pyrrhosoma tenellum is described by Baily as abundant on all the moors of the Penzance district where marshy spots and stagnant pools abound. In June, 1 902, three were taken and many seen by the side of Swanpool, Falmouth. In 1893 C. W. Dale informed Briggs that Ischnura pumilio was common about Penzance, and about that time a presumably local specimen came into the possession of W. E. Baily. Diligent search in 1903 and 1904 failed to discover the haunts of this rare insect. Ischnura elegans is common and generally distributed in the Land's End and Penzance district ; is local about Falmouth and Truro, but of frequent occurrence around Lostwithiel. Stray specimens have been taken in the east of the county, and Norgate records it from Tresco, Isles of Scilly. The female form described by Lucas in which bright orange predominates on the head, thorax, and first two segments of the abdomen, has been taken on the Lynher. Baily records Agrion pulchellum as having been taken sparingly in the Penzance district at Chy-an-hal, Nanscothan, Trengwainton, and Marazion marshes. Agrion puellae has been taken sparingly in the Penzance district by several collectors. It is reported from the south-east of the county and was taken last year near Millook. Of Agrion mercuriale Mr. W. J. Lucas writes to the author : ' Major A. Ficklin gave me a female from near Land's End. I have never recorded it, as the female is so like that of A. puella. I was hoping to see a male later, but Major Ficklin is now dead. Personally I have no doubt about the identification.' 170