INDEX 



871 



Respiration, 71, 87 



direct, 88 



external, 89 



indirect, 88 



internal, 88 

 Respiratory center, 535 

 Respiratory movements, 535 



control of, 535 

 Respiratory pigment, 539 

 Respiratory surfaces, 86, 529 

 Respiratory system, birds, 476 



lamprey, 430 



mammals, 488 



man, 531 



reptiles, 454 

 Respiratory trees, 372 

 Respiratory tube, 431 

 Reie cords, 569 

 Reticular fibers, 55 

 Reticularis, 618 

 Reticulum, 519 

 Retina, 250, 415. 576, 577 

 Retinula, 337 

 Retinuli, 311 

 Retraction, 402 



Reversibility of chemical reactions, 64 

 Resolutions, geologic, 720 

 Rh factor, 545, 679 

 Rhabditoidea. 833 

 Rhabdocoeia. 833 

 Rhabdocoela. 213 

 Rhabdomes. 337 

 Rhabdopleura. 361 

 Rhabdopleuridea. 838 

 Rheas, 481 

 Rhincodon, 436, 839 

 Rhinoceros, 498 

 Rhinoderma, 452 

 Rhipidistea, 840 

 Rhizocephala. 836 

 Rhizopods. 832 

 Rhodesian man. 749 

 Rhodnius, 330, 837 

 Rhodopsin, 580 

 Rhopalia, 193 

 Rhynchobdellida. 835 

 Rhynchocephalia. 458, 840 

 Ribbon worms, 233 

 Riboflavin, 527 

 Ribose nucleic acid, 29 

 Ribs. 474, 508 

 Richards, A. N., 562 

 Ricinulei. 836 

 Rickets, 83, 527, 528 

 Ring canal, 368 

 RNA, 29 



Rocky Mountain revolution, 725 

 Rodentia, 493, 500, 842 

 Rods, 577 

 Root nodules, 758 



Rostral retractor, 224 

 Rostrum, 224, 294 

 Rotaria, 833 

 Rotifera, 220, 222, 833 

 reproduction in, 225 

 Round-dance, 348 

 Roundworms, 227, 806 

 Royal jelly, 347 

 Rumen, 82, 519 



Saccoglossus. 361 

 SaccultJia, 730 

 Sacculus. 581 

 Sacrum, 508 

 Sagittal section, 62 

 Salamanders, 394, 448 

 Salivary glands, 516 

 Salivation, control of, 524 

 Salt, 23 



Salts, concentration of, 24 

 Sand dollars, 374 

 Saprozoic animals, 79, 801 

 Sarcodimi, 148, 157. 832 

 Sarcopterygii, 440, 839 

 Sarcoptes, 835 

 Sarcoptes scabiei, C05 

 Sargassum fish, 442 

 Saurischia, 462, 840 

 Sauropterygia, 456, 840 

 Savanna, 793 

 Sawfish. 434, 437 

 Scala tympani. 584 

 Scala vestibuli, 584 

 Scallop, 258 



Scaphirhynclnis, 440, 839 

 Scaphopoda, 258, 834 

 Scapula, 400, 512 

 Scarlet tanager. 484 

 Scent glands. 506 

 Schistosoma, 810, 833 

 Schizocoele, 1 29 

 Schizocoelom, 238 

 Schizocoelomata, 241 

 Schizocoelous, 381 

 Schizomida, 835 

 Schleiden, M. J.. 11 

 Schoenheimer, Rudolf, 75 

 Schwann, Theodor, 11 

 Scientific literature, 2 

 Scientific method, 3 

 Sclera. 576 

 Scolex, 2 1 6 

 Scorpiones. 835 

 Scorpionida. 321 

 Scrotum. 566 

 Scurvy, 83, 527, 528 

 Scyphozoa, 190, 192, 833 

 reproduction of, 194 



