Preliminary Micro-anatomical Study of the silkworm Larva. I. Nervous System

Abstract

The preliminary light microscopic studies of the third instar larvae of the silkworm were carried out by using modified paraffin technique.  All organ systems were carefully scrutinized under the light microscope.  We are presenting its nervous system to begin with.  The brain structure is fully qualified for the terminology but in a less developed state.  Its nervous system caudal to the head is at its best comparable to the mammalian sympathetic chains placed in the midventral line under the straight G-1 tract beginning from the pharyngeal ganglion to the last one in the tenth body segment.  The brain which lies in the head dorsal to the pharynx is made up of two cerebral halves organized in the fashion shared by mammalian brain, gray matter outside and white matter inside where they communicate in a chiasmatic morphology.  The brain is triangular shape in cross section.  Further studies of the brain are planned.  There are two nerve chains running side by side but coming together at the ganglia.