45^ 



INDEX — GLOSSARY. 



Sense of taste of fishes, 370 

 of insects, 369 

 of man, 372 

 of vertebrates, 370 

 of touch, 364 



of amoeba, 354 

 of weight, 365 

 organs, 77, 325, 353- 

 of amccba, 353-357 

 of arthropods, 361 

 of coclcntcrates, 359 

 of hydra, 358 

 of Nereis, 360 

 of vertebrates, 362 

 special, 311 

 Senses of animals, 404 

 Sensibility, 309 

 Sensory corpuscles, 362 

 Sepal — one of the parts of the calyx, 131 

 Serpent star, 554 

 Sessile — not raised on a stalk. 

 Seta, 279, 346 

 Sex, development of, 182 

 Sexual dimorphism, 219, 220 

 reproduction in hydra, 500 

 selection, 857 

 Sharks, skeleton of, 423 

 Sheep, 666 



Shell of animals, growth of, 730 

 of gastropods, 595 

 of molluscs, 418, 592 

 of turtles, 420 

 Shrew, 652 

 Shrimp, 149, 561 

 Sieve tubes, 11, 74 

 Sight, 366 

 Simiae, 668 

 Siphon, 605 

 Siphonales, 243 

 Siphonaptera, 588 

 Siphonocladiales, 242 

 Siphonophore, 221 

 Sirenia, 652, 667 

 Sirenidae, 639 

 Sitaris, 876 

 Size of organisms, limitation of, 8 



and differentiation, 323 

 Skeletal muscles, 414 

 Skeleton, 325 



and connective tissue, 415 

 cartilaginous, 423, 424 

 of sponge, 520 



of vertebrates, growth of, 734, 735 

 Skull of human embryo, 216 



of vertebrates, 792 

 Slaves of ants, 590 



Numbers refer to paragraphs; Black Fac 



Sleeping sickness, 766 

 Slime mold, 57 



molds — myxomycetes. 

 Sloth, 652 

 Slug, 165 

 Slugs, 602 

 Smell, 366 



Smooth muscle fibre, 414 

 Smut, 253, 259 

 Snail, 164, 165 

 Snails, 595 



fresh water, 602 

 Snakes, 645 

 Snapping turtle, 643 

 Soil and plants, 209-210 



bacteria, 217 

 Soldier (of Aphids), 583 

 Solenoconchaj, 603 

 Sole, symmetry of, 322 

 Somatic tissue, 724 

 Sorus, a cluster of sporangia, 284, 285 

 South American fauna, 826 

 Sparrows, 650 

 Species, 781 



number of, 788 



origin of, 789- 

 Spermatia, 248 

 Spermatogenesis, 183, 185 

 Spermatophyta — spermatophytes, 



170, 292 

 Sperm cells, formation of, 695 



motility of, 697 



nucleus, 698, 699 

 of hydra, 500 



nuclei of pollen, 299 

 Sphagnaceae, 276 

 Sphex, 876 

 Spicules, 522 

 Spider, 569 



web, 844 

 Spiders, polymorphism in, 743 

 Spike, 119 

 Spinal cord, 103, 444 



gangha, 363 



nerves, 444, 445 

 Spindle fibres, 690 

 Spiny ant-eater, 652 

 Spiral valve, 627, 629, 631, 632 

 Spirillum, 227 

 Spirobolus, 158 

 Spirochaete, 227 

 Spirogyra, conjugation of, 693 

 Spirostomum, myonemes of, 88 

 Spleen, origin of, 721 

 Sponge, 129-132 



structure of, 520 

 e numbers refer to figures. 



I 



