The anatomy of the nervous system of the third instar larva ofMusca domestica nebulo fabr. (Diptera-cyclorrhapha-muscidae)

Abstract

The nervous system of the larva consists of a concentrated ganglionic mass lying in the IV and V body segments. This mass is distinguished into a supra-oesophageal portion, the cerebral ganglia, and sub-oesophageal portion, the ventral ganglionic mass. Only one pair of compound nerves originates from the cerebral ganglia. The ventral ganglionic mass is a product of the fusion of the sub-oesophageal ganglion, the three thoracic ganglia and the eight abdominal ganglia. Twelve pairs of nerves arise from the ventral ganglionic mass. Of these, the first pair is of a compound nature, the next three pairs are the thoracic nerves, and the remaining eight pairs are the abdominal nerves. In addition to these segmentally arranged lateral paired nerves, a series of seven unpaired median nerves arise, from the mid-dorsal region of the fused ventral ganglionic mass. Each median nerve soon divides into two secondary nerves on each side, which then accompany the lateral segmental nerves.

The stomodaeal nervous system consists of four unpaired ganglia, connected by an unpaired recurrent nerve. This system innervates the stomodaeum, the salivary glands, the aorta and certain muscles of the mouth parts.