▁min eral isation ▁has ▁preserved ▁the ▁structure ▁of ▁original ▁b one ▁cells , ▁showing ▁individual ▁o ste ocy tes ▁including ▁their ▁inner ▁h ollow ▁spaces ▁and ▁the ▁canal icul i . ▁Also ▁the ▁internal ▁blood ▁vessels ▁of ▁the ▁b one ▁have ▁been ▁preserved , ▁in ▁some ▁cases ▁still ▁empty ▁inside . ▁On ▁some ▁b ones , ▁including ▁some ▁of ▁the ▁sk ull ▁and ▁lower ▁j aws , ▁the ▁peri ost e um ▁is ▁still ▁visible . ▁ ▁Lig aments ▁and ▁cart il age ▁From ▁the ▁nin th ▁cer v ical ▁verte bra ▁to ▁the ▁back , ▁the ▁verte br al ▁joint s ▁show ▁the ▁remains ▁of ▁art icular ▁caps ules . ▁Between ▁the ▁sp ines ▁at ▁places ▁very ▁thin ▁inter sp inal ▁and ▁su pr asp inal ▁lig aments ▁are ▁visible . ▁Six ▁verte bra e ▁are ▁vis ibly ▁c apped ▁by ▁cart il agin ous ▁syn ch ond ros es , ▁a ▁typical ▁ju ven ile ▁feature . ▁Cart il agin ous ▁caps ▁are ▁also ▁present ▁on ▁all ▁lim b ▁joint s , ▁even ▁the ▁smallest , ▁and ▁are ▁especially ▁thick ▁in ▁the ▁shoulder , ▁el bow ▁and ▁w rist ▁joint s . ▁Also ▁the ▁pub ic ▁foot ▁is ▁c apped ▁and ▁the ▁il ium ▁and ▁pub ic ▁b one ▁are ▁separated ▁by ▁cart il age . ▁ ▁Res p ir atory ▁system ▁Of ▁the ▁resp ir atory ▁system ▁little ▁has ▁been ▁preserved . ▁No ▁traces ▁of ▁the ▁l ungs ▁have ▁surv ived , ▁nor ▁of ▁any ▁air ▁s acks . ▁The