TRANSACTIONS OF SECTION H. 599 
different from our own, has been shown to be without justification. If islanders 
can lose the canoe, of what elements of culture can we say that they could never 
be lost? 
2. * Conventionalism’ in Primitive Art. 
By W. H.-R. Rivers, M.D., F.B.S. 
The opinion, almost regarded as a truism in this country, that the geometrical 
patterns of primitive art have arisen through the conventionalisation of natural 
objects, is by no means universally accepted. Boas and others in America hold 
that the movement may take place in the opposite direction, features of a con- 
ventional design suggesting ideas which find their expression in naturalistic 
representations. The German historical school believe that designs often regarded 
as stages in a process of conventionalisation are merely examples of the mixture 
of motives belonging to different peoples, and it is believed that a transition is 
as likely to take one direction as the other. Others, again, see a sufficient 
explanation of the changes which occur in purely technical considerations. 
In Polynesia and Melanesia we can be confident that the general direction of 
change is from naturalistic representations to geometrical patterns. Series of 
objects can be found with intermediate links wholly inexplicable on any other 
hypothesis. Nevertheless, the various psychological factors implied by the term 
‘conventionalisation’ do not furnish a complete explanation. Such factors as 
economy of labour or inexactness in copying would account for simplification or 
for degeneration into all kinds of meaningless and irregular forms. They cannot 
account for the coming into being of definite geometrical patterns, sometimes 
even more complicated than the objects from which they have been derived. 
Similarly, purely technical factors are insufficient. The nature of material or 
implements may help to explain why a process of change should be in the direc- 
tion of straight or curved lines, and the nature of the surface to be decorated 
may account in some measure for the degree of complexity of the final pattern. 
Such motives, however, are insufficient to explain why, for instance, the human 
figure should become in one place a lozenge and in another a set of concentric 
circles or even a spiral; ‘why in one place it is the face or eye and in another the 
limbs which persist in geometrical form. The direction taken by the process 
of conventionalisation cannot be explained purely by psychological or techno- 
logical factors, but in many cases at least the motive must be sought in the 
interaction of peoples possessing different forms of artistic expression. 
Thus, the art of the Banks Islands in Melanesia is most naturally to be ex- 
plained as the result of the interaction between two peoples : one coming from 
elsewhere, whose art was devoted to the expression of humanand animal forms; 
the other an aboriginal population, whose designs consisted chiefly of simple 
rectilinear patterns. The transition from the representation of a man to such 
a figure as the lozenge is to be explained by the greater persistence of the 
aboriginal form of expression as the art introduced by the immigrants was trans- 
mitted from person to person, and from generation to generation. Similarly, the 
transition from the frigate-bird te the scroll pattern of the Massim is to be 
explained by the mixture of a people to whom the frigate-bird was a predominant 
object of interest with one whose geometrical art had taken the spiral and other 
curvilinear forms. 
Conventionalisation, as a term for changes due to the saving of labour, in- 
exactitude in copying, and other similar factors, is a process which has played 
a large part in the history of art, but for the special directions taken by the 
process we must look to factors arising out of the blending of cultures. 
3. Notes on the Magic Drum of the Northern Races. 
By Davi MacRitcum. 
In the shamanistic ceremonies of the races occupying the northern parts of the 
Eurasian continent and of the Japan Islands, the sacred drum has long been 
used as a medium enabling the priest to place himself en rapport with the spirit 
world. By this means he can not only divine the future, but he can also ascer- 
tain synchronous events occurring in foreign countries. He can also, by its aid, 
