690 



INVERTEBRATA 



Strepsitene thread, tlefinition of, 4 

 Strobila of .1 mrtin, 72 

 Stabilization, 75 ; definition of, 7'2 

 Strongylocentrotus, 511, 630; egg of, 3; 



eutelechy of, 21 



Strongylocentrotus droebachiensis, 505 

 Strongylocentrotus franciscanus, 505 

 Strongylocentrotus lindus, 504, 506 

 Strongylocentrotus pnrpi'mtus, 505 

 Sub-genital pit, formation of, in Aurelia, 



71 

 Sub - intestinal ganglion, formation of, in 



Paludina, 315 

 Sub-neural gland, formation of, in Ciona 



intestinalis, 625 ; in blastozooid of Uro- 



chorda, 639 

 Sub-neural sinus, formation of, in Peripatus 



capensis, 174 

 Sub-oesopliageal ganglion, formation of, in 



Ag>:/i-iin. 232, 235 ; in the Scorpion, 241 ; 



in Teri-liratiilinit x<-/i/t-iit,-i<->iinlit;, 412 

 Sub-stomachal canals, formation of, of Beriie 



94 

 Suli-tentacular canals, formation of, in Jie,;',, , 



94 

 Sucker (internal sac), formation of, in Cypho- 



nautes larva, 392 



Sucker muscles of Cyphonautes larva, 393 

 Sucker of Cyphonautes larva, 401, 406 ; 



e version of, 394 

 Sucking tube, formation of, in Achthcres am- 



bloplitis, 207 

 Supporting lamella of Urticiiia crassicurnix, 



79 

 Supra-intestinal ganglion, formation of, in 



Paludina, 315 

 Supra-oesophageal ganglion, formation of. 



in Siii/itin h!i>niicta-ta, 432 ; in Tere- 



bmtulina sepfe/ifrimiaUs, 411 

 S)/candrn raphanus, later development of, 



43 ; segmentation of the egg of, 35 

 Syconidae, 37 

 Symmetrical post-larval stage of Anomura, 



216 



Symphyla, 280, 281 

 S//nnpt/i, 547, 565 



Synapfn </////////<>, development of, 529-541 

 ^i/iiapta vivipam, 529 ; development of, 



539-541 

 Syncarida, 177 

 Syndesis, definition of, 4 

 Synizesis, definition of, 4 



Tactile organ of Sagitta bi^inii'tntn, 433 

 Tadpole of Ascidians (Tuuicata), 654 ; of 



simple Ascidiau, 619-622 

 Tadpoles, determination of sex of, 17 

 Taemolae of larva of Aurelia, 69 ; of Beroe, 



94 ; of medusa of Tubular ia, 58 

 Tail, formation of, in larva of Ainptu'<i.>-iix 



in nceolatus, 596 ; in CaUidina ri'ssco/n. 



423 ; in embryo of Cynthia partita, 618 ; 



of Spermatozoon, definition of, 7 ; of l.irv;i 



of Tuuicata (Urochorda), 608 



Tail-bud, formation of, in larva of Amphioxus 



lancculatUK, 596 

 Tail-eudoderm, origin of, of larva of Cynthia 



partita, 614 



Tardigrada, 169 ; development of, 243 

 Teeth, formation of, in Echinus esculentus, 



515 



Teleostei, 22 



Telescoped development, definition of, 153 

 Teloblast of Oriodrilus lucuum, 158 ; of 



Nephelis, 161 ; of Poh/unr/Iius, 144 

 Telolecithal egg, definition of, 26 ; of Cepha- 

 lopoda, 354 ; of Scorpion, 239 ; of Peri- 

 jiKti's, 177 



Telotroch of Tornaria larva of .Brtfr/;/n//Ax//.v 

 clavigerus, 574 ; formation of, of larva of 

 Dreissensia, 337 ; in larva of Patella, 299 ; 

 in Actinotrocha larva of Phoronis, 381 ; 

 in larva of Polygordius, 140, 144 

 Telotrochal larva, definition of, 153 

 Telson, formation of, in Astacus, 189 

 Tendon-cells, metamorphosis of, in larva of 



Galcnicella id mi, 208 

 Tentacle pockets, formation of, in CaUinnira, 



95 

 Tentacle-sheath of Bur/nla, development of, 



in bud, 397 



Tentacles, formation of, in Antedon rosacea, 

 550, 551 ; in Callianira. 95 ; in Paludina, 

 315 ; in Pedicellina echinata, 403 ; in 

 Phascolosoma, 379 ; in Actinotrocha larva 

 of Phoronis, 381 ; in adult Phoronis, 383 ; 

 in Polygordius appendiculatus, 148 ; in 

 medusa of Tubularia, 58 

 Terebellidae, 157 

 Terebelliformia, 128, 153 

 Terebratidina septi n/,-i,,,i<>lis, development 



of, 407-413 

 Teredo, 348 

 Terguni, formation of, in Cirripedia, 202 ; 



in Li mains, 238 ; in Scolopendra, 283 

 Terminal jihites, formation of, in Amplii urn 

 squamata, 499 ; in Asterina gibbosa, 478 ; 

 in Echinus esculentus, 517 

 Terminal threads of ovaries, formation of, in 



Phyllodromia, 263 



Tertiary radial plates, formation of, in Ante- 

 don rosacea, 556 



Test, formation of, in simple Ascidian, 622 

 Test-cells in larva of simple Ascidian, 622 

 "Test-cells " (follicle cells), in egg of (.'i/nthia 

 partita, 610; of Pyrosoma, 632; of Salpa, 

 635 



Testicardines, 406, 407 



Testis of A scar is megalocephala, 438 ; forma- 

 tion of, of Molgula, 628 

 Tetrads, definition of, 12 

 T-giants, development of, of Ascaris mcgalo- 



cephala, 448, 449 

 Thalassinidae, 215 

 Thaliaceae, 568, 608, 635, 636, 637 

 Thaumatocrinus, 560 



Theca, formation of, in Caryophyllia cyaihus, 

 87 



