I. A study of the arteries of the brain of the spiny anteater ( Echidna aculeata ), to illustrate the principles of arterial distribution

Abstract

Previous investigations into the arterial supply of the brain may be divided into two classes depending in great part on the nature of the material and on the methods employed. Firstly, there are investigations which have been primarily concerned with the determination of the exact limits of supply of individual arteries to particular regions and structures of the brain ; and secondly, there are investigations whose purpose has been to enquire into the morphology of the vessels without particular regard to the exact area of supply of the vessels, which is either inferred or neglected. The two classes of investigations find their parallel in the series of researches which led to the development of the theory of nerve components. The writings of Charcot (1883), Duret (1874), Beevor (1909), Stopford (1915) and others, are the best examples of the first class. Whilst these writers have not altogether neglected the topographical features and variations of the arteries outside of the brain, they have attacked the problem of arterial distribution with, the avowed intention of determining its clinical significance. Their attention has therefore been concentrated on discovering the field of arterial supply within the brain, the relative automony of these fields and the amount of variation present. Naturally the material which has been used by them has been almost exclusively human.