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lar to, but somewhat rougher than that experienced on moving the 

 fingers along the mucous lining of the ileum in man. 



By microscopic examination, this was found to arise from the pre- 

 sence of numerous villous-looking bodies projecting from the free sur- 

 face of the skin. These were about half the size, and somewhat of 

 the shape, of the villi met with in the human intestine. They 

 appeared as long saccular projections from the skin, filled with granu- 

 lar non-nucleated corpuscles. The outline of each was dark, sharp, 

 and depended evidently on the presence of a distinct limitary mem- 

 brane. I could detect no cellular forms on the outer or free surface 

 of these bodies : they resembled in their general outline the villi of 

 the choroid plexus, but there was no apparent cavity and no trace of 

 vessels in their interior. 



The limitary membrane of these bodies presented on its inner sur- 

 face delicate hexagonal markings, analogous to those met with in the 

 middle or basement membrane of the scales of the Percidce : I was 

 unable, however, to trace the structural relations of that membrane to 

 the other tissues of the skin. 



These bodies would seem to possess a definite, though as yet 

 unexpressed, relation to the various maturely developed dermal 

 appendages. 



Glands. 



These are formed by inflections of the primary or germinal mem- 

 brane and its epithelium ; and are situated in the textures of the skin, 

 on the free surface of which they terminate by open mouths, Some 

 of these openings are visible to the naked eye ; others require the aid 

 of the microscope for detection : the former are confined to the lateral 

 line ; the latter are of two kinds, — the one studded over the whole 

 surface of the skin, — the other found only around the anal orifice. 

 These openings are the orifices of follicles or glands, — the first and 

 last superficially, the second deeply seated in the structure of the 

 skin. 



The glands of the lateral line are continued onwards to the head, 

 with the ossicles of which they communicate by branched and com- 

 plicated diverticula. It is to these glands, as they are found along 

 the lateral line of the body, that I shall confine my present observa- 

 tions. These vary from four to nine lines in length, the chief portion 

 of which lies in a direction nearly parallel to the surface of the skin. 

 The orifice is about half the diameter of the body of the follicle, 



