Chapter V: Part II: Structure and habits of trilobites 77

Internal organs and muscles 77
Alimentary canal 77
_Ceraurus pleurexanthemus_ 79
_Calymene senaria_ 80
_Cryptolithus goldfussi_ 80
Summary 81
Gastric glands 82
Summary 84
Heart 85
_Illænus_ 85
_Ceraurus_ and _Calymene_ 85
The median "ocellus" or "dorsal organ" 86
Nervous system 89
Various glands 89
Dermal glands 89
Renal excretory organs 90
Reproductive organs 90
Panderian organs 90
Musculature 91
Flexor muscles 92
Extensor muscles 92
Hypostomial muscles 94

Eyes 96
Summary 97

Sex 98

Eggs 98

Methods of life (See also under "Functions of
the Appendages") 98
Habits of locomotion 99
Food and feeding methods 103
Tracks and trails 104