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 A HISTORY OF CORNWALL of exceptional value. During 1901 and 1902 several of the Truro students made collections of the Cornish wasps and bees in different parts of the county, and did much to extend our knowledge of their occurrence and distribution. In spite, however, of willing helpers at the schools and elsewhere, the following list is in all probability very imperfect, and the north coast will have to be much more systematically and continuously examined before any claim can be made that the Cornish list of Hymenoptera Aculeata is even approximately complete. Sixteen species of ants, representing eleven genera, are found in the county. Two of these, namely, Monomorium pharaonh and Cremastogaster scutellaris are introductions. The former, in spite of its minute size, is a troublesome pest on provisions in several houses at Falmouth. The latter has been found in greenhouses at Penryn. Among the indigenous ants the commonest of course are Formica rufa, with its great mound-like nests; the subterranean Formica fusca, which in Bishop's Wood, near Truro, occasionally deserts the ground and takes possession of the stump and roots of cut-down trees ; Lasius fu/iginosus, with its nests in decaying timber ; Lasius flavus, nesting under stones ; the aphis-loving Lasius niger, with its extensive subterranean galleries ; and the several races grouped together as Myrmica rubra. Lasius umbratus appears to be scarce, and has so far been found only near Fowey. Tapinoma erraticum, a carnivorous ant that, according to Forel, attends the fights between other ants as an interested spectator, and when permitted drags off the body of the vanquished to serve as food, occurs near Land's End, and was found by Dale at Scilly. Several stray examples of the rare Ponera contracta have been taken on two different occasions in dry moss at Mount Edgcumbe ; Myrmedna latreillei was obtained by Dale at Hurst Castle, Fowey ; and last year a small colony was found in the same locality. Tetramorium caespitum is not uncommon round the coast, occurring at Boscastle, Newquay, on the cliffs near Tol-pedn-penwith, and with its inquiline Loxotropos tritoma, on the sea-slope at Downderry. Stenamma westwoodi was found some years ago at Mount Edgcumbe, and in 1900 several were obtained in a nest of Formica rufa in Bishop's Wood, Truro. A solitary worker of Leptothorax acervorum was found at Sandplace, near Looe, in August, 1901. The Fossores are represented in the county by eighty-three species belonging to twenty-six genera. The apterous female of Mutilla europaea was twice taken near the mouth of the Looe valley about twenty years ago, one was obtained at Calstock a few years later, and it has been taken thrice during the past six years at Bishop's Wood, Truro. The winged male was found in the valley of the Gannel, near Trevemper bridge, in the summer of 1903. Methoca ichneumonides with its curious ant-like female, is a rare and usually a local insect. In Cornwall, though scarce, it is widely spread. It occurs along the bank of the Lynher in the company of Myrmosa melanocephala, has lately been taken near Crackington Haven, and also at Newquay and Perranporth. One male was taken near Truro in 1904, and twenty years ago Marquand captured two on Trevaylor Heath, near the Land's End. Both species of Tiphia have been taken sparingly throughout the county, but in spite of an increased number of collectors not one has been recorded for the last five years. Pompilus bicolor was obtained by Baily from the neighbourhood of Penzance, and by Rothney in June, 1902, at Newquay. P. cinctellus was remarkably common in 1891 round Carbis Bay, but though still found in the county at Newquay and elsewhere, has for some years completely deserted the St. Ives district. P. consobrinus was one of Marquand's captures in the Land's End district, and has once been taken since in the neighbourhood of Gulval. P. unguicularis occurs in the valley of the Gannel, near Newquay, and has been taken several times in the vicinity of Truro. Salius affinis has been obtained by Bignell at Whitsand Bay, has been captured twice near Truro, and is found not unfrequently along the north coast from Newquay to Crackington. S. notatulus was taken near Looe in 1900, and again in 1904. Agenia bircana has been several times mentioned as a Cornish species, and examples occur in an old reputedly Cornish collection at Falmouth, but without any details as to their origin. The fortunate capture of a female near Bude in July, 1905, however, puts its claims as a county species beyond dispute. Trypoxylon attenuatum is occasionally common in favoured spots in the east of the county, but is irregular in its appearance. In 1902 it was plentiful, in 1903 not a single specimen was recorded, in 1904 it was scarce, and in 1905 again common. Spilomena troglodytes was first recorded by Marshall from Botus Fleming, and has subse- quently been taken at least thrice between the Bodmin Moors and the Tamar. Its small size may cause it to be overlooked by the inexperienced. Gorytes tumidus has been obtained occasionally along the south coast from Mount Edgcumbe to Land's End. G. campestris has been reported from Calstock, but the two specimens were accidentally destroyed before their identification was corro- borated. G. bidnctus has been captured near Cargreen, and several times in the Land's End district. Nysson interrupts has been found by Bignell near Liskeard. A silvery-looking bee was noticed last year several days in succession near the same spot on the towans at Perranporth, and on capture proved to be the rare Oxybelus mucronatus. This species has also been taken by Nevinson at Holy- well Bay. The extensive genus Crabro is well represented in the county. C. tibialis occurs near Trebartha ; C. cetratus has been taken on the Lynher, and in favourable years C. capitosus, though 182