These are formed from bony plates embedded in the dermis which are overlain by horny ones and are partially fused with the ribs and spine.
ðiːz ɑːɹ fˈɔːɹmd fɹʌm bˈoʊni plˈeɪts ɛmbˈɛdᵻd ɪnðə dˈɜːmiz wˌɪtʃ ɑːɹ ˌoʊvɚlˈeɪn baɪ hˈoːɹni wˈʌnz ænd ɑːɹ pˈɑːɹʃəli fjˈuːzd wɪððə ɹˈɪbz ænd spˈaɪn.