bum py " ▁surface ▁that ▁inter digit ates ▁with ▁the ▁e pid erm is , ▁strength ening ▁the ▁connection ▁between ▁the ▁two ▁layers ▁of ▁skin . ▁ ▁In ▁the ▁pal ms , ▁fingers , ▁sol es , ▁and ▁to es , ▁the ▁influence ▁of ▁the ▁pap illa e ▁project ing ▁into ▁the ▁e pid erm is ▁forms ▁cont ours ▁in ▁the ▁skin ' s ▁surface . ▁These ▁e pid erm al ▁rid ges ▁occur ▁in ▁patterns ▁( see : ▁finger print ) ▁that ▁are ▁gen et ically ▁and ▁ep igen et ically ▁determined ▁and ▁are ▁therefore ▁unique ▁to ▁the ▁individual , ▁making ▁it ▁possible ▁to ▁use ▁finger print s ▁or ▁foot print s ▁as ▁a ▁means ▁of ▁identification . ▁ ▁Ret icular ▁region ▁The ▁ret icular ▁region ▁lies ▁deep ▁in ▁the ▁pap ill ary ▁region ▁and ▁is ▁usually ▁much ▁th icker . ▁It ▁is ▁composed ▁of ▁dense ▁irregular ▁connect ive ▁t issue , ▁and ▁receives ▁its ▁name ▁from ▁the ▁dense ▁concentration ▁of ▁col lagen ous , ▁el astic , ▁and ▁ret icular ▁fib ers ▁that ▁we ave ▁throughout ▁it . ▁These ▁protein ▁fib ers ▁give ▁the ▁der mis ▁its ▁properties ▁of ▁strength , ▁extens ibility , ▁and ▁el astic ity . ▁ ▁Also ▁located ▁within ▁the ▁ret icular ▁region ▁are ▁the ▁roots ▁of ▁the ▁hair s , ▁se b ace ous ▁g lands , ▁swe at ▁g lands , ▁re cept ors , ▁n ails , ▁and ▁blood ▁vessels . ▁ ▁T atto o ▁in k ▁is ▁held ▁in ▁the ▁der mis .