812 



INDEX 



Sea-firs (Sertularians), 144 



Sea-hares, 702 



Sea-mats, 333 See Polyzoa 



Sea -mice, 464 



Sea-mussel, 678 



Sea-pens, 194 



SEA-URCHIN, External features, 386, 

 387, 388 : Corona, 388 : Aristotle's 

 lantern, 389, 390 : Nervous system, 

 390, 39 J : Ambulacral system, 391 : 

 Enteric canal, 391, 392 : Ccelome, 

 392 : Blood-vascular system, 392 : 

 Reproductive organs, 392 : Develop- 

 ment, 392 : Systematic position, 406 



Sea-urchins, 403* See Echinoidea 



Secondary axis, 42*, 43 



Secondary ectoderm, 304 



Secretion, 26* 



Segment, 43* 



Segmental organ See Nephridium 



Segmentation of oosperm, 23* 



Segmentation - cavity See Blast o c oele 



Segmentation-nucleus, 21*, 22 



Seison, 328 



Seisonida, 322 



Selenaria, 340 



Selenariidce, 342, 345 



Self-mutilation, 425 



Semostomse, 176*, 181, 182, 224 



Sense Organs, 39* : Obelia, 136 : Tra- 

 chylinse, 154, 155 : Aurelia, 171, 

 172 : Cubomedusae, 181 : Hormi- 

 phora, 213 : Ctenoplana, 221 : Tjal- 

 fiella, 222 : Platyhelminth.es, 263 : 

 Nemertinea, 289: Chsetognatha, 311, 

 312 : Brachionus, 320 : Rotifera, 

 327 : Starfish, 370 : Sea-urchin, 

 388 : Nereis, 437 : Lumbricus, 448 : 

 Sipunculus, 487 : Hirudo, 501, 502 : 

 Hirudinea, 507 : Apus, 523, 524 : 

 Astacus, 542 : Crustacea, 581, 582 : 

 Peripatus, 594 : Periplaneta, 611 : 

 Insects, 629, 630 : Scorpio, 643, 

 655 : Arachnida, 653, 654. 655 : 

 Mussel, 673, 674 : Pelecypoda, 689, 

 690 : Amphineura, 698, 699 : Triton, 

 712 : Gastropoda, 726, 727 : Sepia, 

 749, 750 : Nautilus, 765 : Cephalo- 

 poda, 774 See also Eyes, Auditory 

 organs, Olfactory organs, Gustatory 

 organs, Tactile orgams, Osphradia 



Serse papillae, 296, 485 



SsriA, External features, 738, 739 : 

 Shell, 740, 741 : Chromatophores, 



741 : Mantle-cavity, 741 : Internal 

 skeleton, 742 : Alimentary system, 



742 : Ink-sac, 744, 769 : Vascular 

 system, 744 : Coelome, 745 : Ctenidia, 

 745, 746 : Nervous system, 745, 746, 

 747, 748 : Sensory organs, 749, 750, 

 751 : Excretory organs, 751, 752 : 

 Reproductive organs, 752, 753, 754 : 

 Systematic position, 767 



Sepia cultrata, 738, 739, 740, 741, 742, 

 743, 748, 747, 748, 750 



Sepiidce, 767* 



Septal funnel, 173* 



Septai neck, 755* 



Septibranchia, 678*, 679, 680 



Septum, 202* 



Serialaria, 340 



Serosa, 613*, 644 



Serpula, 457, 462, 465, 468, 476, 477 



Serpulidcr, 457, 461, 473, 475, 476 



Sertularians, 144 



Setae, 428, 430, 431, 445 : provisional, 

 363, 443 



Setigerous sac. 431*, 442, 443, 445, 446 



Sexual dimorphism, 40* 



Sexual generation, 141 



Shell, Magellania, 353, 354, 355 : 

 Brachiopoda, 360, 361 : Mussel, 

 664, 665 : Pelecypoda, 680 : Chiton, 

 695, 696 : Triton, 702, 703, 704 : 

 Gastropoda, 717, 718: Scaphopoda, 

 736 : Sepia, 740, 741 : Nautilus, 

 754, 755 : Cephalopoda, 770, 771 



Shell -gland, 240, 515, 674, 776, 778 : 

 (Apus), 515*, 522* : (Crustacea), 581 



Shelly loop, 354* 



Ship-worm, 678 



Shrimp, 514, 555, 572, 573 



Sicula, 166* 



Sigaretus, 720 



Silicispongiae, 125* 



Silicoflagellata, 75 



Silver-fish, 616 



Sinupalliata, 678*, 681, 690 



Sinupalliate shells, 681* 



Sinus, 541 



Siphon, 391, 419, 704 



Siphonal process, 704* 



Siphoniata, 693 



Siphonodentalium, 736 



Siphon oglyphe, 185* 



Siphonophora, 143*, 159, 160, 161, 162, 

 163, 164, 165, 166, 224 



Siphonozooid, 200* 



Siphons, inhalant and exhalant, 664*, 

 680 



Siphtmcle, 754* 



Sipunculoidea, 365, 484*, 511, 512: 

 Example of the class, 484 : Dis- 

 tinctive characters, 488 : General 

 organisation, 488 : Body-wall, 488 : 

 Alimentary canal, 489 : Blood- 

 vascular svstem, 489 : Nervous sys- 

 tem, 489 : Eyes, 489 : Nephridia, 

 489 : Reproductive organs, 489 : 

 Development, 489, 490 : Distribu- 

 tion, Affinities, &c., 490; 512 



SIPUNCULUS NUDUS, General external 

 features, 484, 485 : Body-wall, 485 : 

 Ccelome, 486 : Blood-vascular sys- 

 tem, 487 : Alimentary canal, 486, 

 487 : Nervous system, 486, 487 : 



