The lamination of the masseter muscle in the Japanese serow (Capricornis crispus).

The lamination of the masseter muscle in 21 Japanese serows of different sexes and ages was studied by the method of Yoshikawa et al. who proposed a lamination theory for this muscle. The masseter muscle in the Japanese serow was found to be composed of I) the proper masseter muscle which included 1) the first superficial, 2) the second superficial, 3) the intermediate and 4) the deep masseter muscles, in which the deep masseter muscle could be subdivided into a pars anterior and pars posterior and II) the improper masseter muscle which included 5) the maxillomandibular and 6) the zygomaticomandibular muscles, in which the maxillomandibular muscle was further divided into first and second layers. These findings indicate that the lamination of the masseter muscle in the Japanese serow is the same as that in the goat and sheep.