137. The evidence at present stands thus: There are numerous multipolar cells which have no traceable connection with nerve-fibres; and fibres which have no direct connection with multipolar cells. By the first I do not mean the disputed apolar cells, I mean cells in the gray substance of the centres which send off processes that subdivide and terminate as fibrils in the network of the Neuroglia (Figs. 16, 18). It is indeed generally assumed that these have each one process--the axis-cylinder process--which is prolonged as a nerve-fibre; nor would it be prudent to assert that such is never the case; though it would be difficult to distinguish between a fibre which had united with a process and a fibre which was a prolongation of a process, in both cases the neuroplasm being identical. I only urge that the assumption is grounded not on anatomical evidence, but on a supposed necessary postulate. All that can be demonstrated is that some processes terminate in excessively fine fibrils; and occasionally in thousands of specimens processes have been traced into dark-bordered fibres. It is true that they often present appearances which have led to the inference that they did so terminate--appearances so deceptive that Golgi and Arndt independently record observations of unbranched processes having the aspect of axis cylinders being prolonged to a considerable distance (600 μ in one case), yet these were found to terminate _not_ in a dark-bordered fibre, but in a network of fibrils.[166]