The tracheal supply to the central nervous system of the wetaHemideina thoracica(White)

Abstract

Abstract The tracheal supply to the wet a central nervous system, from the spiracles to the intraganglionic tracheoles, has been revealed with deposited cobalt sulphide. In conformation with the general orthopteran plan, air is delivered to the head via a pathway kept separate from the rest of the body. All ganglia comprising the central nervous system are connected to spiracles through wide-bored tracheae. Extensive abdominal air sacs ensure adequate ventilation throughout the primary tracheae, including the ventral longitudinal tracheae from which the thoracic ganglia are directly supplied. In the abdomen an additional series of air sacs inserted between the ventral longitudinal tracheae and the ventral connectives ensures a good circulation of gases in tracheae travelling along the abdominal connectives. All ganglia from the brain to the terminal abdominal ganglia are surrounded by air sacs. Within the ganglia the neuropile is provided with dense tracheation; tracheae circle around the neuropile, sendi...