Animal Morphology. 137 



and the ultimate nerve distributions in the several senses, 

 as well as the cineritious matter of the brain and spinal 

 cord,. are analogues of muscular fibrillae or true muscular 

 structure. Thus the brain and spinal nerves, with their 

 ultimate nerve distribution, are considered in their differen- 

 tiations as morphologies of muscle. 



Though it may seem strange, yet the muscles of voluntary 

 motion are viewed as differentiated brain, responding to the 

 cineritious or grey matter of the brain and spinal cord ; and, 

 to speak in a figure, are a species of conscious or recipro- 

 cating agents to the brain, outside the domain of its own 

 special conscious agency. 



Again, for the brain to be truly invergent, the right ought 

 to change for the left, which is the case, the left side of the 

 brain ruling the right side of the body. 



It is with extreme regret that, in speaking of the senses of 

 force, touch, and want, no better authority can be given, so- 

 far as the writer knows, than those contained in the Edinburgh 

 Monthly Journal of Medicine for 1855, including the numbers 

 of February, March, and April, the title of the article being 

 " Upon an Experimental Inquiry into the Existence of a 

 Sixth Sense ; " and in 1859, for March, April, May, some 

 further researches, including suggestions in relation to a 

 seventh sense, in the Edinburgh Medical Journal, by the 

 same author. 



Whether from an over-weaning fondness for one's own 

 child, or from a fair and honest examination of the 

 contents of these articles, the writer will not attempt to- 

 decide : but length of time has rather confirmed him in 

 his original researches, than led him to doubt or abandon 

 them. For instance, in the sub-kingdom we naturally ask, 

 Of what good would the sense of touch be to the common 

 crab, save in the fragmentary form of the antennae, with its. 

 hard and stony shell ? But force to such a creature would 



