554 COMPARATIVE ANATOMY AND PHYSIOLOGY* 



Perennichordata, 87 



Perigonimus ; figure, 37 



Peripatus; figure, 64: gnathites, 

 127; blood-vessels, 189; tra- 

 chese, 215 ; nephridia, 257 ; skin, 

 299 ; appendages, 302, 377 ; ner- 

 vous system, 401; sensory or- 

 gans, 434, 417 ; gouads, 498 



Perissodactyla, 99 



Petronayzon, 88 



Pkolas, 80 



Physalia, 41 



Pbysoklisti, 92 



Physophora ; figure, 41 



Physostomi, 92 



Pipa ; tongue, 153 



Plinaria, 49 



Platyhehnintb.es, 49 ; gonads, 485 



Pueumodermon, 82 



Podophthalmata, 70 



Podura, 75 



Polia, 85 



Polychseta, 54 ; larva, 539 



Polynoe, 54 



Polyodon, 91 



Polyplacophora, 81 



Polypterus, 92 ; brain, 421 



Porifera, 35 



Primates, 100 ; limbs, 356 



Pristis ; teeth, 142 



Proneomenia ; nervous system, 

 401 ; gouads, 502 



Proteus, 93; gill, 236 



Prototheria, 98 ; vertebrae, 317 



Protozoa, 25 ; digestion, 103 ; 

 parasitic, 177 ; contractile va- 

 cuoles, 247 ; phosphorescence, 

 270 ; movements, 371 ; repro- 

 duction, 473 ; skeleton, 274 



Protracheata, 65 



Pteropoda, 81 



Pycnogonoidea, 74 



Pyrophorus ; phosphorescence, 270 



Pyrosoma. 88; phosphorescence, 

 270 



R .bbit ; caecum, 172 ; brain, 42 1 ; 

 taste-bulbs, 438 ; placenta, 515 



Radiolaria; yellow cells, 272; 

 skeleton, 276 



Ratitse, 97 ; feathers, 368 



Reptiles, 96 ; teeth, 145 ; salivary 

 glands, 159; oesophagus, 162'; 

 intestine, 169 ; heart, 196 ; lungs, 

 239 ; respiration, 245 ; kidneys, 

 261 ; brain, 422 ; sensory organs, 

 437, 454, 467, 471 ; gonads, 512 



Rhizocephala, 69 



Rhizocrmus, 63 



Rhizopoda ; skeleton, 276 



Rhyncopygus ; anus, 121 



Rodents, 99 ; teeth, 150 



Rotatoria, 50 ; digestion, 118 ; re- 

 spiration, 230 ; nephridia, 251 



Ruminants ; stomach, 166 ; retia, 

 209 



Sabella, 55 



Sacculina, 69; nutrition, 178 



Sagartia, 39 ; section of, 111 



Salamaudra, 93 ; ribs, 345 



Salmon ; teeth, 144 



Salpa, 88 



Sargus ; teeth, 142 



Sarsia, 40 



Sauropsida, 95 ; uric acid, 265 ; 

 vertebral column, 314, 321 ; 

 skull, 331 



Scaphopoda, 82 



Scarus ; teeth, 142 



Scorpion; gnathites, 127 ; mouth, 

 179 ; lung-books, pectiues, 226 ; 

 poison, 266 



Sea-gull; gizzard, 176 



Selachoidei, 91 



Sepia, 83 



Serpula, 55 



Siuupalliata, 80 



Siphonophora, 41 



Sirenia, 99; respiration, 2 13; ver- 

 tebrae, 317; limbs, 353 



Snakes ; teeth, 146 ; arterial ar- 

 ches, 205 



Solen, 80 ; haemoglobin, 212 



Spitangidse, 63 



Spide/ ; poison glands, 265 ; silk 

 organs, 267 



Sponge, 31 ; digestion, 106 ; re- 

 spiration, 211; nitrogenous 

 waste, 248 ; skeleton, 278 ; sense - 

 cells, 431 ; gonads, 483 



Squatina ; heart, 196 



Squilla ; figure, 69 ; testis, 498 



Steatornis ; syrinx, 391 



Steganophthalmata, 42 



Stenostomata, 96 



Stentor, 30 ; stentorin, 272 



Strepsiptera, 77 



Streptopeura, 81 



Stylasteridae ; dactylozooids, 109 



Suctoria, 31 ; digestion in, 104 



Sun-birds ; tongue, 156 



Sycon, 36 



Synapta, 64 ; spicules, 296 



Taenia, 49 ; digestion in, 177 ; 

 plasmatic canals, 185 ; develop- 

 ment, 545 



