POPULATION— COMMUNICATIONS mens ; the greatest rarities are among the hymenoptera. The submarine ^^pop/iilu!: Bou- nalrei has been found at Penzance. Of crustaceans and molluscs there are plenty, many being rare. Students should turn to the writings of Jonathan Couch, Brooking Rowe, Cornish, E. H. Rodd, Peach, R. Q. Couch, Isabell, Marquand, Bate, Tregelles and others. III. Population and Communications If we may judge from prehistoric and later remains, Cornwall was once more thickly populated than it is at present, and the populated areas were different. The duchy is now, for its size, one of the most thinly peopled of English counties. Places now al- most uninhabited, such as the Bodmin Moors, give signs of a considerable population in the past; while in desolate spots like the sands ot Perranzabuloe lie thousands of human remains, in burial-places that have been desecrated by the elements. A neolithic burying-ground has recently been discovered at Harlyn Bay. But it is impossible from things like this to gain anything like a true estimate of former popula- tion. One thing is certain; the working of tin in the early days of the Bronze Age proves a settled and stationary population, at a time when agricultural populations were chiefly migratory. The earliest tangible evidence is given by the Domesday survey, in which the II