Nervous system of poultry lice, Lipeurus lawrensis tropicalis Peters (Phthiraptera: Ischnocera)

The anatomy and histology of nervous system of Lipeurus lawrensis tropicalis (Phthiraptera: Ischnocera) is described in detail. The brain is U-shaped compact unit. It is tilted backwards to cover the tritocerebral commissure, circumoesophageal conncetives and a large portion of sub-oesophageal ganglion. The ventral nerve cord consists of sub-oesophageal ganglion and three thoracic ganglia. The abdominal ganglia are wanting and the abdomen is innervated by the nerves arising from the metathoracic ganglionic mass. Interganglionic connective are absent between the thoracic ganglia, but the sub-oesophageal ganglion and the prothoracic ganglion are connected by interganglionic connectives. The origin and disposition of different nerves arising from metathoracic ganglion show that it is a compound ganglionic mass, in which abdominal ganglia are also fused. From this ganglionic mass three pairs of nerves are given in thoracic segments and three pairs to the abdominal segments. The frontal ganglion is situated anterior to the brain at a considerable distance. The histology of the brain and that of thoracic ganglion is also described.