396 
Pepsin, 224 
Pericardial cavity, 14, 123 
fluid, 269 - 
Pericardio-peritoneal canals, 123, 271 
Pericardium, 124, 269 
Perichondrium, 39 
Periderm, 25 
Peridural space, 152 
Perilymph, 186 
duct, 186 
Perimeningeal space, 151 
Perimysium, 21, 128 
Perineurium, 20 
Periosteum, 24, 39 
Peripheral nervous system, 161 
Peristalsis, 207, 227 
Peritoneal canals, 124 
cavity, 14, 123 
Peritoneum, 124 
Permanent dentition, 211 
Peroneal artery, 288 
Perpendicular plate of ethmoid, 100 
Pes, 116 
Pessulus, 255 
Petrosal bones, 67 
ganglion, 175 
Petrotympanic fissure, 74 
Phzochrome cells, 352 
Phalanges, 116 
Pharyngeal bones, 80 
derivatives, 245 
plate, 205 
tonsils, 247 
Pharyngobranchial, 65 
Pharynx, 207, 222, 236 
Phosphorescent organs, 28 
Photophores, 28 
Phyllospondylous, 47 
Physiology, r 
Physoclistous, 248 
Physostomous, 248 
Pia mater, 152 
Pigment cells, 22, 26 
layer of eye, 198 
Pigmented epithelium of eye 2o0r 
Pillar cells, 186 
Pinealis, 147 
Pisiforme, 117 
Pituitary body, 148 
Placenta, 318, 351 
vitelline, 348 
Placoid scale, 40 
Plantigrade, 120 
Plasma, blood, 265 
Plastron, 41 
Platybasic skull, 61 
Platysma myoides, 134 
Pleura, 124 
Pleural cavities, 123 
rib, 53 
Pleurapophysis, 46 
Pleurocentrum, 47 
Pleurodont, 88 
INDEX. 
Pleurodont dentition, 213 
Plexus, chorioid, 144 
Plexuses, 163 
Plica fimbriata, 219 
semilunaris, 203 
Plume, 31 
Plumule, 31 
Pneumatic bones, 96 
duct, 248 
Pneumatocyst, 247 
Pneumogastric nerve, 176 
Podium, 116 
Poison glands, 27, 221 
Pollex, 117 
Polymastism, 37 
Polyphyodont denition, 211 
Pons (Varolii), 150 
Pontal flexure of brain, 144 
Popliteal artery, 288 
Pori abdominales, 124, 322 
Portal circulation, 277 
heart, 294 
vein, 277 
Postbranchial bodies, 246 
Postcardinal vein, 279 
Postcava, 290 
Postclavicle, 106 
Posterior chamber of eye, 203 
column of cord, 139 
cornua, 139 
fissure of cord, 139 
horns of cord, 139 
lymph sac, 303 
Postfrontal bone, 69 
Posthepatic digestive tract, 206 
Postminimus, 118 
Postorbital bone, 69 
Postotic nerves, 175 
Postparietal bone, 69 
Postpermanent dentition, 212 
Postpubic process, 112 
Post-temporal bone, 106 
fossa, 71 
Post-trematic nerves, 175 
Postzygapophysis, 46 
Precava, 300 
Predentary bone, 88 
Prefrontal bones, 69 
Prefrontals of birds, 96 
Prehallux, 118 
Prehepatic digestive tract, 206 
Prelacteal dentition, 212 
Premaxillary bone, 70 
Premolars, 213 
Prenasal bone, 100 
Preoperculum, 77 
Prepollex, 118 
Prepubic process, 111 
Presphenoid, 67 
Presternalia, 109 
Pretrematic nerves, 175 
Prevertebral ganglia, 163 
Prevomer, 69 
