Muscle architecture of the elongated nose in the Asian elephant (Elephas maximus)

The architecture of the M. caninus in the elongated nose was examined in th e Asian elephant (Elephas maximus). The following complicated musculature o f the M. caninus was observed in the proximal and distal regions of the nos e: (1) Proximal region: In the superficial layer, the longitudinal bundles are confirmed in the dorsal part, and the obliquely-oriented ones in the ve ntral part. In the middle layer, some bundles run ventro-distally, while ot her ones represent longitudinally-oriented running. The deep layer consists of complicated architecture of many bundles. Some muscle bundles run medio -laterally, while the others extend proximo-distally in this space. (2) Dis tal region: In the dorsal part of the M. caninus, the bundles run at deep-s uperficial direction, while in the ventral part the bundles are longitudina lly arranged. The bundles run at lateral direction near the septum of the n asal conduits. The N. facialis and N. infraorbitalis send many branches in the lateral area of the M. caninus in the trunk. This muscle architecture o f multi-oriented bundles and well-developed innervation to them suggest tha t they enable the elongated nose to act as a refined manipulator in the Asi an elephant.