27 



interesting in this connection. Stephaneuj •) describes an extensive 

 network of nerve-fibers, which he fonnd in the skin of reptiles. 

 This network built up of non-medulhited fibers is easily distinguish- 

 able from the familiar subepithelial plexus, which lies deeper and 

 in which only an interlacement of nerve-fibers, for the greater part 

 still mednllated, takes place. The relations of the non-medullated 

 network to the subepithelial plexus are also desci'ibed minutely by 

 him. In the former, which spreads diffusely as a true network of 

 nerves in the skin, he describes by the side of very few other 

 endings an "organo di senso in stato diffuso," a conception which 

 is the more plausible since the network is immediately connected 

 with an intrapapillary extension of the same nature. 



Here lies the link that joins Stephanelli's publication to thai of 



VlTALI. ') 



ViTALi examined the skin of the nail-bed also after Ruffini's gold- 

 chloride method. His results correspond completely with those of 

 similar researches by Ruffini and others. In succession he describes 

 the presence of many free endings easy to differentiate by the very 

 melodious Italian names: gomitoli, alberelli, espansioni ad anse 

 avoiticciati, fiochetti papillari, grappoli, and also of Ruffini's, 

 Meissner's and Vater-Pacini's corpuscles. The principal interest now 

 hinges about the fact that he lays particular stress upon the 

 occurrence of anastomoses between the terminals reciprocally and 

 upon their contact, as a whole, with the refe amielinica subpapil- 

 lare, therewith emphasizing the importance attached by Ruffim 

 long since to the ultraterminals as expounded in his teoria unitaria 

 previously mentioned. Finally Vitali comes to the conclusion that 

 all those terminals together with the rete subpapillare form one 

 connected amyelinic meshwork. When following up the Italian school 

 a little further, we shall see that this meshwork must be placed on 

 a level with Stephanelli's diffuse network. Then also the various 

 endorgans of the higher vertebrates will be found to be i)oints of 

 difïerentiation amidst less developed surroundings. "Eche cos'altra 

 sono," as »Simonelli puts it rhetorically, "quello die noi denomigniano 

 espansioni, se non il condensarsi in punti limitati di nn simile 

 reticolo diffuso periferico : in altri termini se non punti nodosi e 



AuGUSTO Stephanelli. Nuovo contributo alia cogno.scenza della espansioni 

 sensitivi dei Rettili e considerazioni sulla tessitura del sislemo nervoso periferico. 

 Intern. Monatschrift. f. Anat. u. Pliys. XXXII 1916. — Sui dispositivi micros 

 copici della sensibilita cutanea a nella mucosa orale del Rettili. (Ibid. XXXII 1916). 



~) G. Vitali. Contributo alio studio istologico dell ungliia. Le cxpansioni nervose 

 del derma solto ungeaie dell" uomo, (Ibid. XXXII 1915). 



