PALINURUS OR THE SPINY LOBSTER OF BOMBAY. 383 

 In Palinurus the concentration is still further marked. The brain 



Fig.. 



Eig. 



Fig. 8.— Nervous system of 



PALINURUS. 



Fig. 9.— Nervous system of palindrus in* bitu. 



= Ophthalmic nerve. 



1 = Antennulary „ 



II = Antennary „ 



III = Mandibulary „ 



IV to XIX = Nerves to Segments. 

 BR = Brain. 



t = Thoracic ganglion. 



a v N = Anterior visceral nerve. 



AN = Median root of anterior visceral nerve or azy 



gos nerve. 

 A o c = Anterior oesophageal commissure. 

 Loc = Circum oesophageal ,, 



p o c = Post-cesophageal M 



T A c = Thoracico abdominal „ 



p v N = Posterior visceral nerve. 

 SA = Opening for sternal artery. 

 8 = Stomach h nrnedasMe . 

 G = Gut ) 



or supra oesophageal ganglia form a large two-lobed mass close 

 behind the eye-stalks. It sends out three large pair of nerves, the 

 ophthalmic, the antennulary and the antennary whose course is suffi- 

 ciently described by their names. Posteriorly it sends a para- 

 oesophageal (Gr. para, near, beside) commissure on each side of the 

 gullet to join a large elongated ganglionic mass on the floor of the 

 thorax. 



