Key to organ systems and organs: 



CHORD AT A 



a skin and general subjects 



b exoskeleton 



c teeth 



d hair, horns, nails 



e feathers 



f sense organs 



g glands 



h mammae 



i pigment cells 



EVERTEBRATA 



1 Integument 



a skin and general subjects 



b exoskeleton 



c teeth, bristles, etc. 



d sense organs 



e glands 



f tentacles, suckers, etc. 



g pigment cells 



2 Nervous system 



a general subjects 



b central nervous system 



1 brain 



2 spinal cord 



c accessory organs 



1 paraphysis 



2 parietal organ 



3 pineal body 



4 hypophysis 



5 saccus vasculosus 



6 other accessory organs 

 d ganglia 



1 cephalic ganglia 



2 spinal ganglia 

 c nerves 



1 cephalic nerves 



2 spinal nerves 



f visceral nervous system 



1 para- and sympathetic 

 nervous system 



2 intramural nervous system 

 g meninges 



a general subjects 



b diffuse nervous system 



c centralized nervous system 



1 ganglia 



2 nerves 



3 nerve net 



d accessory organs 



3 Special sense organs 



a olfactory organs 

 b visual organs 



1 eye 



2 lens 



c auditory and static organs 

 d other sense organs 



230 



a chemoreceptors 



b visual organs 



c auditory and static organs 



d other sense organs 



