pa·le·on·tol·o·gy 
(pā′lē-ŏn-tŏlə-jē)
(pā′lē-ŏn-tŏlə-jē)n.
The study of the forms of life existing in prehistoric or geologic times, as represented by the fossils of plants, animals, and other organisms.
pa′le·on′to·logic (-ŏn′tə-lŏjĭk), pa′le·on′to·logi·cal (-ĭ-kəl) adj.
pa′le·on·tolo·gist n.