



. :iinl tli. -cte.l \\i- 



vent rally. of these the latter arises 



166 of the primary basis of the nail. In Into and 



ungulate V, rtel,iat.> it (fig. 294 ah) ; {>ed to a great ex ' 



in Mm it atrophies, and is recognisable only in an exceed! 

 r. -tliu-i ! condition as nail-welt. "By this term is meant the 

 thickening of tin- epid- rinis which forms the tr. 



t th nail t<* tli.' corrugated skin of the ball of the fine 

 nail | 'la to, on the contrary, is from the beginning exclusively a 

 product of til.- dorsal Mil-fan- of the basis of the nail. There Is 

 MI -it In -i- in Man nor in other Mammals a dorsal migr 



be tcnninal fundament of the i a degeneration of 



ftte *p*4 



Fig. 298. Fig. SO*. 



Fig. 293. -A, Longitudinal lection through the to of a Ceroopithoeo* B, Longitudinal 

 through the second finger of Macaoua ater. A/let GCUCXUAIK. 

 I l.l.tu : , .. plantar horn (Sohlenborn) ; nw. nail-wall. 



Pig 294 Section through a Dog'i to*. Aft*r GEGEXBAC*. 

 IV, Nail-plate; th, plantar horn ; 6, ball of too. 



its v. nti-al portion, which otherwise furnishes a more complete 



plantar horn. 



So far as regards the particular events in the development of 

 the nail-plate, the struct mv is demonst i able in human embryo 

 month- old ai a thin Mat layer of cornified, closely united cells on 



1 - urface of 1 1 i y basis of the nail or the bed o; 



nail. It is prod no d by the mucous layer upon which it 

 mediately lies, but oontintiei t'.ra time to be covered by the : 

 corn, ous layer that i> piv- nt at all points of tlie .jad'-rmi>. This 

 invt>tnnnt I NNA'R cpoiiychium is not lost until the fifth month. 

 llouev. i. notwitli>tandinu r their invr>tm.-nt. th- naiN are easily 

 -ni-abl,. >,,u, ,- wt.-ks beforr this fnnu thi-ir \vliiten- .^. in dis- 

 tiiH'tit;ii from the nddi-h <>r dark red color c-! i : .nir skin. 



