INDEX. 369 
Muscles of chela, 93 Ovary, 31, 129 ‘ 
of stomach, 57 structure of, 131 
Myosin, 186 Oviduct, 129 
Myotome, 174 Oviposition, 351 
Mysis, 281, 323 
relicta, origin of, from Jf, 
oculata, 327 
Mysis stage of development, 280 
N. 
Natural History, 3 
Philosophy, 3 
Nauplius stage of development, 
215, 280 
Nearctic province, 314 
Nephrops, 259, 332 
Nerve, 101 
auditory, 117 
optic, 118 
Nerve-cells, 103, 187 
fibres, 101, 188 
Nervous system, 105 
development of, 213, 224 
functions of, 354 
Noble crayfish, see Astacus nobilis 
Nomenclature, binomial, 13, 15 
Norway lobster, see Vephrops 
Novozelanian province, 314 
Nucleated cell, 199 
Nucleolus, 187 
Nucleus, 177, 200 
changes of, in cell-division, 200 
0. 
Csophagus, 51 
Olfactory organ, 114 
Organ, 22 
Origin of crayfish, evidence as to, 
320, 331 
Ovisac, 132 
Ovum, 129 
structure of, 133 
P. 
Palzarctic province, 314 
Palemon, 268, 328 
Palinuride, 263 
Palinurus, 261, 264 
Palp, 171 
Paranephrops, 250, 306, 313 
Paraphragm, 158 
Parasites of crayfish, 356 
Parastacida, 252, 256, 306, 313 
Parastacus, 250, 306 
Pemphia, 341 
Peneus, 267, 280 
Pericardium, 69 
Perivisceral cavity, 50 
Phyllobranchia, 271 
Physiology, 46 
Pleurobranchia, 79 
Pleuron, 96, 143 
Podobranchia, 75, 165 
Podophthalmia, 279 
Pore-canals, 195 
Post-orbital ridge, 233 
spine, 232 
Potamobiida, 252, 256 
Prawn, see Palemon 
Prehension of food, 49 
Procephalic lobes, 160 
development of, 213 
Propodite, 165 
Protopodite, 143 
Prototroctes, 315 
