124 



On the Teuminatioxs of the Nerves at the Peiiiphery and 

 in the different Organs, or the Terminations of the 

 Nervous System in general. By M. N. Jacubowitscii. 



(' Comptes reiidus,' May 7, 1860, p. 859.) 



I. If a portion of the mesenteiy of the cat, Avith the Paci- 

 nian corpuscles contained in it, be placed for twenty -four 

 hours in some of Moleschott^s solution (alcohol and acetic 

 acid), and then spread out upon glass, and submitted to the 

 microscope under a magnifying power of from 180 to 200 

 diameters, it will distinctly and clearly exhibit not only the 

 Pacinian corpuscles, but also the vessels of every kind 

 surrounding them, as well as the cellular -tissue-corpuscles 

 Avith their nutrient vessels ; in fact, the whole of the histo- 

 logical elements composing the mesentery will be seen. The 

 Pacinian corpuscles are composed of two capsules, an external 

 and an internal. The nerve itself usually divides, before 

 entering the corpuscle, into several branches, which retain 

 their medullar}^ substance and their neurilemma until they 

 reach the corpuscle, and even viutil they have penetrated 

 the external capsule and reached the internal, whence the 

 axial cylinder, now completely isolated, continues its course to 

 the summit, where it terminates in a very distinct cell, and 

 even into the nucleolus itself of the cell. In one case I was 

 fortunate enough. to witness the rupture of the internal capsule, 

 and the escape of the cell with its membrane and contents — 

 the nucleus and nucleolus, — a fact which establishes in an 

 evident manner their existence as a termination of the 

 nerve. Moreover, I would farther remark, that in many 

 preparations 1 have seen not one cell only forming the 

 termination of the nerve, but even several. 



II. a. When the corpuscula tactils, properly so termed, 

 are treated with Moleschott's solution, they not only become 

 transparent, but the elements of Avhich they are constituted 

 are disintegrated. Thus, in the frog's thumb, we see elon- 

 gated, fusiform, distinctly nucleated cells, in the form of a 

 cup, into which the nerve enters, losing its medullary sub- 

 stance on its entrance, and retaining, as in the case of the 

 Pacinian corpuscles, only its axial cylinder, in order to 

 terminate in a nerve-cell, and, as in that case, in the nucleus ; 

 and in such a way as to show the existence of an essential 

 analogy between the Pacinian corpuscles and the corpuscula 

 tactils. 



b. The nerve having entered the cutaneous papilla, after 



