AN editorial note in Antiquity of March, 1939, directs attention to an important development in the study of European prehistoric chronology. E. H. de Geer, it is stated, has succeeded in equating the growth-rings of trees from the ancient mound of Rakenhangen in the Romerike district of Norway with those of a giant Californian sequoia on one hand, and with clay varves from Angermanland in North Sweden on the other. The tree trunks examined were preserved when a shaft was sunk to the base of the mound in 1868. The investigation points to A.D. 931 as the date of the cutting of the trees and the erection of the mound. As the editor of Antiquity poults out, the acceptance of the full implication of this important discovery must await further critical examination; while the application of dendrology to European chronology is not without its peculiar difficulties. The March issue of this enterprising periodical well maintains its high standard of interest, in part owing to the inclusion of Prof. V. Gordon Childe's lecture on the relations of India to the West before the time of Darius, which originally was delivered before the Warburg Institute on October 10, 1938, and Dr. R. E. Mortimer Wheeler's report on his excavations in Brittany, to which reference has already been made in NATURE (see NATURE of March 4, p. 386). The report is fully illustrated and accompanied by plans. Mr. James Hornell draws on his world-wide knowledge of the construction of various forms of boat to trace the plank-built boat to its origin. Among the interesting shorter notes which are always a feature of the contents, mention should be made on this occasion of a valuable suggestion from Mr. Stanley Casson, urging the prosecution of submarine research in the coastal waters of Greece. He points out that not only are the sea routes of antiquity well known, but recent discoveries of statuary, especially bronzes of the best period of classical art, support the argument that cargoes of artistic loot on the way to Rome may have been lost with some frequency.