INDEX 



669 



Apical string in larva of Bcdanoglossu.s 

 clavigerus, formation of, 573 



Aplysia, 324 



Appendages of branchial hearts of Loligo, 

 development of, 364 



Appendages, formation of, in embryo of 

 Agelena, 225 ; in embryo of Astacus, 

 183; in embryo of Donacia, 252; in 

 embryo of Peripatus capensis, 171 



Appendages of Trilobita, 239 



Appendicular sinus in Peripatus capensis, 174 



Aptera, 245, 263, 265 



Apus, 200 ; ancestral, origin of, 212 ; com- 

 pared to Zoaea, 211 



Arachnactis, larva of Cereanthidae, 85 



Arachnida, 169, 177, 204, 205, 251, 254, 

 285, 662 ; development of, 221-244 



Araneina, 221 



Archaeocytes of Plakina, 44 



Archenteron, formation of, in embryo of 

 Antedon rosacea, 545; inlnrva. of Asterias, 

 461 ; in larva of Asterina gibbosa, 472 ; in 

 embryo of-Distaplia, 632; in larva of 

 Echinus esculentus, 507 ; in larva of Holo- 

 thuria tnbulosa, 541 ; in Peripatus capensis, 

 171 ; in embryo of Pyrosoma, 633 ; in larva 

 of Sytiapta digitata, 531 ; in Terebratu- 

 lina septentrionalis, 409 ; segmentation 

 of, in embryo of Antedon rosacea, 546 



Archiannelida, development of, 128-153 



Archicerebrum of Scolopendra, 283 



Archinephridium of larva of Eupomatus, 154; 

 formation of, in larva of Polygordius, 138, 

 140, 144 ; of Polygordius lacteus, 152 



Arenicola, 129, 153 



Arenicolidae, 157, 168 



Argiope, 416, 455 



Argiope neapolitana, 407 



Aristotle's lantern, formation of, in Echinus 

 esculentus, 515 



Arms, formation of, in Antedon rosacea, 

 556; in Asterias, 469, 470; in Asterina 

 gibbosa, 474 ; in Ophiothrix fragUis, 492 ; 

 in Solaster, 482 ; iu Terebratulina sep- 

 tentrionalis, 413 



Arrow-worms, 428 



Arthropoda, 455, 655, 656, 661, 662 ; cuticle 

 of, 19 ; development of, 169-290 ; fossil 

 representativeVef-j 20 



Arthrostraca, 177 



Artificial parthenogenesis of eggs of Echi- 

 noidea, 524 



Ascaris, 659 



Ascaris megalocephala, development of, 437- 

 447 



Ascidiacea, 568, 608 



Ascidiacea compositae, 568, 609, 637, 646 



Ascidiacea luciae, 568, 609, 632, 637 



Ascidiacea simplices, 568, 609, 637, 646 



Ascidians, 98 ; eggs of, 11 



Ascidian tadpole, 65 



Ascidiozooids of Pyrosoma, 640 



Asconidea, 37 ; development of, 46, 47 



Asexual germ, definition of, 2 



Asexual reproduction in Urochorda, 637-646 



Aspidobranchiata, 291, 301 



Asplanchna Herricki, 418 



Asplanchuidea, 418 



Astacidae, 213 



Astacus, 191, 194, 195, 197, 198, 223, 



230, 235, 236, 243, 281 

 Astacus fluviatilis, development of, 178-189 

 Aster, formation of, from middle piece of 



spermatozoon, 9 

 Asterias, 474, 475, 476, 477, 478, 483, 484, 



485, 487, 495, 503, 506, 507, 514, 525, 



569 ; development of, 460-472 

 Asterias glacialis, 464, 466, 472, 492, 505 

 A sterias pallida, 457 



Asterias rubens, 457, 461, 464, 466, 472, 529 

 Asterias vulgaris, 401, 457, 464, 465, 472 

 Asterina gibbosa, 457, 482, 495, 536, 569, 



656 ; development of, 473-481 

 Asteroidea, 287, 456, 494, 495, 496, 497, 



498, 500, 501, 502, 503, 514, 515, 518, 



520, 521, 522, 523, 530, 531, 533, 535, 



538, 541, 543, 560, 563, 564, 565, 569, 



585 ; development of, 457-484 

 Astropecten, 457 

 Astropectinidae, 472 



Asymmetry of post-larval Pagurid, 65, 216 

 Atrial cavity, formation of, in Amphioxus 



lanceolatus, 599 ; in Molgitla ampulloides, 



632 ; in Ascidiozooid of Pyrosoma, 640 ; 



in Blastozooid of Urochorda, 638 

 Atrial folds, formation of, in larva of A mphi- 



oxus lanceolatus, 599 

 Atrial iuvaginatiou, formation of, in larva 



of simple Ascidian, 620 ; in larva of 



Doliolum, 637 ; in embryo of Pyrosoma, 



634 



Atrial tube of embryo of Pyrosoma, forma- 

 tion of, 634 

 Atrium, formation of, in bud of Bugula, 



397 ; in embryo of Membranipora, 389 ; 



in embryo of Pedicettina echinata, 400 ; 



in larva of Pedicellina echinata, 400 ; 



in Physa (outer stomodaeum), 323 ; in 



larva of Synapta digitata, 536 

 Atrochal larva, definition of, 153 

 Auditory organ of Astacus, 189 

 Aurelia, development of, 67-73 

 Auricle of heart, formation of, in Cyclas, 350 ; 



in Loligo, 362 

 Auricularia larva, 561, 574, 585 ; structure 



of, 533 

 Axial organ, formation of, in Antedon rosacea, 



552 ; in Asterina gibbosa, 480 

 Axial sinns, formation of, in Asterina gibbosa, 



475 ; in Echinus esculentus, 510 

 Axolotl, 656 



Azygous tentacles of Antedon rosacea, forma- 

 tion of, 556 

 Azygous tube-feet, formation of, in Asterina 



gibbosa, 476 ; in Echinus esculentus, 518 : 



in Ophiothrix fragUis, 492 



Balanoglossida, 568, 569, 575, 585, 589, 662 



