INDEX 



945 



Spermatophores, 171, 493 

 Spermatophoric sac, 2 62 

 Spermatotheca, 246, 353 

 Spermatozoa, 104, 115, 407 

 Sphaeiella, 66 

 Sphaeriidae, 256 

 Sphenethmoid bone, 518 

 Sphenisciformes, order, 586 

 Sphenodon, 546, 548, 869 



punctatum, 560 

 Sphenodontia, suborder, 548 

 Sphincter, 644 

 Sphyraenidae, family, 453 

 Spicules, 121. 125 



types of, 125 

 Spider, digestive system, 293 

 Spiders, 266, 292 

 crab, 295 

 comb-footed, 295 

 orb- web, 296 

 Spinal cord, frog, 527 

 Spiny dogfish, circulatory system, 4d2 

 Spiracles, 349, 422, 427 

 Spiral valve, 422 

 Splanchnic mesoderm, 536 

 Splanchnopleure, 815 

 Splenial bones, 495 

 Sphnts, 874 



Sponge, histology of, 126 

 metabolism, 127 

 reproduction of, 127 

 Sponges, 26, 119 



diagrams of different types, 124 

 economic relations, 129 

 fresh \Yater, 121 

 phylogeneuc aavances, 129 

 Spongilla, 121 

 Spongin, 125 

 Spongioblasts, 125 

 Spongioplasm, 60 

 Spongovostox apicedentatus, 320 

 Spoonbills, 446 

 Sporoblasts, 74 

 Sporocyst, 756, 758, 759 

 Sporogony, 73 

 Sporont stage, 750 

 Sporosac, 135 

 Sporozoa, 111 



class, 72 

 Sporozoites, 74 

 Sporulation, 74, 90, 749 

 Springtails, 265, 312 

 Spruce-moose biome, 725 

 Squalus acanthias, 422 



internal anatomy, 429 

 Squamata, order, 547, 551 

 Squamosal bone, 494, 518 

 Squamous epithelium, 107 

 Squash bug, 318 

 Squid, dissection of, 261 



eye of, 262 

 Squirrels, 623 

 Stapes, 403 



Stapliylinidae, family, 340 

 Starfish, 226 



development, 232, 234 

 metamorphosis, 232 

 regeneration, 234 

 Starling. 595 



Statoblasts, 187 „„ „„„ 



Statocysts, 121, 133, 159. 253, 262, 276 

 Statolith, 159, 253 

 Stauromedusae, order, 137 

 Steapsin. 385, 502 

 Stegocephalia. 869 

 Stegomyia. 80 

 Stem-mother, 112 



Stenopelmatus fasciatus, 312 

 Stenostomvim, 160 

 Stentor. 7 0. 71 



regeneration, 681 

 Stereoblastula, 807 

 Sternal artery, 272 

 Sternebrae, 644 

 Sternum. 268, 306. 345 

 Sticklebacks, 451 

 Stigma, 81 

 Stigmata, 366 



Stimuli, classes, 848 ' 



Sting, 357 



ray, 423, 456 

 "Stingaree," 425 

 Stipes, 345 



Stomach, ruminant, 633 

 Stomodeum, 140, 158 

 Stomolophus, 138 

 Stone canal, 221, 230, 231 



flies, 265, 321 

 Strawberry leaf roller, 326 

 Strecker's frog, 482 

 Strepsiptera, order, 265. 333 

 Streptostylic condition. 547 

 Strigiformes, order, 593 

 Strix varia, 593 

 Strobilization, 140 



Strobilops labyrinthica texasiana, 240 

 Strobilus, 763 

 Strobula, 139. 140 

 Strongylocentrotus. 222 

 Strongyloidea, order, 176 

 S.rongyloides stercoralis. 176 

 Struggle for existence. 885, 886 

 Struthio camelus, 584 

 Struihioniformes, order, 585 

 Sturgeons, 446 

 Sturnus vulgaris, 595 

 Stylommatophora, 258 

 Stylonychia. 71 

 Stylopids, 265 



Subclavian veins of frog, 508 

 Subesophageal ganglia, 275 

 Subgenital plates. 348 

 Sublittoral zone. 713, 770 

 Submentum, 345 



Subpharyngeal ganglion, 199, 208 

 Subumbrelia, 132 

 Succession. 727 

 Succinea avara, 240 

 Suckers, 450 

 Suctoria, 70, 72 

 Suidae, family, 632 

 Sunfishes, 454 



Sunlight, biological effects, 700 

 Superciliary crest, toad, 540 

 Supraclavicle, 465 

 Supracondyloid fossa, 640 

 Supraoccipital bone, 465 

 Suprapharyngeal ganglia, 199 



ganglion. 208 

 Suprarenal glands, 671 

 Suprascapula of frog, 521 

 Surra, 80 „„. „„„ 



Survival of the fittest, 88o, 886 

 Sustentative tissue, 106 

 Suture, 343, 641 

 Swans, 589 

 Sweat glands, 616 

 Swifts, 593 

 Swimmerets. 270 

 Swimming clam, 284 

 Sycon, 124, 125 



Sylvilagus. cotton tail rabbit, bZ7 

 Symbiont, 340 

 Symbiosis, 144, 735 



