| IX. Nervous system |
|
|
|
|
|
|
|
|
|
|
|
| • | A. Ventral,
ladder-like |
|||||||||
| • | B. Cephalized with cerebral
ganglia |
|||||||||
| • | C. Ocelli (eyespots) present in
some |
|||||||||
| – | detect light, dark, movement |
|||||||||
| • | D. Rheoreceptors - detect water
movement |
|||||||||
| • | E. Chemoreceptors throughout
epidermis |
|||||||||