l] Material n IK/ Mct/iotfn of Examination 5 



fibres is substituted, it becomes necessary to take more than one photograph sometimes 

 as many as tour of the cortex before the structure of the whole depth is completely shown, 

 anil tlir subsequent joining together of the several prints is difficult and unsatisfactory. 



There- is a strong demand for the reproduction of a series of drawings showing types 

 of fibre arrangement in various cortical regions, not only because our knowledge of cortical 

 fibre arrangement deserves to be placed on an equal footing with that of the nerve cells, 

 but because all the efforts which have been made hitherto in this direction have been of 

 a crude description. Even the plates published by Kaes are no more convincing than 

 diagrams, a figure of Passow's is very rough, in Obersteiner's text-book there is but one 

 exceedingly exaggerated figure of the cortical fibres, a drawing of Andriezen's, compounded 

 from Oolgi and Weigert-Pal specimens, is extremely diagrammatic although it has been copied 

 into several text-books, and in Ramon y Cajal's work on the auditory area is the only 

 passable representation of the nerve fibres in a Weigert-Pal specimen of the cerebral cortex, 

 which I have come across, and concerning this drawing we are not enlightened as to the 

 exact part from which it was taken : and this leads up to a point which requires special 

 emphasis, namely, that it is of essential importance in any anatomical or pathological disser- 

 tation, illustrated by drawings or microphotographs showing the lamination or condition 

 of nerve fibres or nerve cells in the cerebral cortex, to indicate, by a diagram or a carefully 

 worded description, the precise spot from which the specimen represented was taken, so 

 that if at any time a subsequent worker may wish to examine the cortex, he may take 

 sections from corresponding positions and utilise the illustrations as standards of comparison. 

 It is unfortunate that the beautiful illustrations of nerve cell lamination for which we are 

 indebted to the late Carl Hammarberg fail in this respect. 



