1893.] NEW-YORK MICROSCOPICAL SOCIETY. 69 



I, 2, 3 by means of which we calculate and heap up dollars. 

 Should the ganglion of a, in the so-called claustrum, be destroyed 

 by a blood effusion, the capacity of pronouncing or writing an a 

 is lost. Should the ganglion of number 3 be destroyed, the 

 idea of number 3, or the capacity of writing it, will be lost. 

 From these facts the inference can be made that the ganglionic 

 bodies are central organs for concrete or positive facts ; whereas 

 the gray substance is central for diffuse nerve action, such as 

 fancy, religion, dreaming, fears, hopes, etc. The gray matter of 

 the frontal lobe is the seat of intelligence, as first maintained by 

 Th. Meynert, the regulation of our acts by judgment and adapta- 

 tion. Hence all mental diseases — disturbances of the intellect — 

 are located in the frontal portion of the brain. 



In all nerves running from the central organs to the periphery 

 of the body the most essential and only conducting thread is the 

 central axis cylinder, which is either bare, such as in non- 

 medullated nerves, or supplied with a sheath of nerve fat, or 

 myelin — an insulating substance seen in the medullated nerves, 

 furnishing them with a whitish tint, due to the opacity of the 

 myelin in surface illumination. The axis cylinders, I said, have 

 a delicate reticular structure. Any nerve, though originally 

 medullated, will, upon approaching the surface, lose its myelin 

 coat and split up into a number of extremely delicate so-called 

 axis fibrillae, best rendered conspicuous by a stain of chloride of 

 gold, introduced into histological technique by the late Jul. 

 Cohnheim, of Germany. All we can recognize on such axis 

 fibrillae, with the highest powers of the microscope, is a beaded 

 or rosary-like appearance, a series of minute dots, interconnected 

 by the most delicate threads. Evidently this feature is a reti- 

 culum transformed into a linear projection of threads and gran- 

 ules, eminently fit for contraction. I exhibit here the cornea of 

 a cat, stained with chloride of gold, showing the axis fibrillae 

 as they inosculate with the protoplasmic formations, termed 

 cornea corpuscles. 



With these facts at hand we may reasonably assert that what 

 we call nerve is a complex reticulum of living matter, either ar- 

 ranged diffusely, as in the gray substance ; or condensed into a 

 bulky formation, termed ganglionic element ; or arranged in rows, 

 as in the axis cylindeis ; or in a linear projection, as the axis 



