124 SPECIAL HISTOLOGY. 



loops which I have figured are blood-vessels. He has only 

 imperfectly seen the nerves of the papilla? in question, perhaps 

 on account of his having preferred the use of caustic soda, 

 which more easily destroys them. Latterly, in making very 

 delicate investigations, I have used only acetic acid, and have 

 arrived at the following results: — Each point of a papilla, or 

 each papilla with an axile corpuscle, generally contains two, or 

 as frequently happens at the points of the fingers four, dark- 

 bordered tubules, which, surrounded by a neurilemma which 

 has escaped previous observers, pass upwards through the axis 

 of the papilla to reach the base of the axile corpuscle, as a fine, 

 convoluted nervous twig of 0*006 — -012'" in thickness. Here 

 the nerve frequently becomes invisible, so that, as has hap- 

 pened to Wagner, one may be led to believe that it enters the 

 corpuscle, which is seated upon it, as upon a stalk, and there 

 ends. However, if a number of fresh preparations be treated 

 with acetic acid and examined, the conviction is soon arrived 

 at that this is merely apparent, the nervous tubules in reality 

 proceeding along the outer surface of the corpuscle, either as 

 far as its point, or very nearly so. In the meanwhile they 

 either remain together or take an isolated course. In both 

 cases their neurilemma becomes excessively delicate, appearing 

 finally to vanish entirely, while the nerves themselves surround 

 the axile corpuscle, passing round it either more directly, 

 though in a slightly undulating course, or forming one or 

 several spiral-coils (fig. 54, B). As regards the actual termi- 

 nation of the nervous tubules, I retain the opinion I formerly 

 expressed, inasmuch as, in at least six cases, I have again most 

 distinctly seen loops (fig. 54). It is, however, always difficult 

 to observe them, and very frequently impossible, in spite of 

 every exertion; and therefore, as we are all liable to error, I 

 will blame no one for considering the termination of the nerves 

 of the papillae to be unknown, or for believing in the existence 

 of free ends, which perhaps also exist, and, at any rate, very fre- 

 quently appear to exist. I only state what, according to mj 

 best belief, I have seen; and while I have no prejudice in 

 favour of loops, neither can I see anything alarming in their 

 existence. This much, however, is certain, that Wagner has 

 not traced the nerves in the papillae so far as they may be 

 traced, and therefore, at present at all events, can lay no claim to 



