INDEX 



685 



Phylaetolaemata, 385, 386, 396 



Phyllocarida, 177 



Phyllodromia, development of genital organs 



of, 262, 263 

 Phyllopoda, 177. 185, 193, 211, 655 ; larval 



history of, 200-201 

 Phyllosoma, larva of Loricata, 214 

 Physa, 291, 312, 320, 323, 338, 340 

 I'hi/.iiitia, 64 



Pilidium larva, 118, 164 ; ancestral signific- 

 ance of, 127 ; development of, of Cere- 



tii-Ktitlus lacteus, 120 ; metamorphosis of, 



122-124 ; resulting from fragments of egg 



and isolated blastomeres, 125 

 Pinnules of Antedoti rosaceu, formation of, 



557 

 Piriform organ, formation of, in Cyphonautes 



larva, 390 

 Pisidium, 349 

 Placenta, formation of, in embryo of Sal fin, 



635 



Plaice, 22 



Plakiiia, development of, 44 

 J'lanocera, 161,332 ; development of, 103-112 

 /'fm/fn-bis, 322 

 Planula larva, definition of, 60 ; developed 



from egg of free Medusa, 60 ; of Siphono- 



phora, 65 ; compared to embryo of Cteno- 



phora, 96 ; interpretation of, 98, 99 

 Platvctenea, 53 

 Platj helminthes, 118, 157, 161, 164, 320, 



424, 600, 635, 661 ; development of, 102- 



117 ; evolution of, 115-117 

 Pleopods, formation of, in Astacus, 188 

 Pleural ganglia, formation of, in Dreissensia, 



342 ; in Lolir/o, 358 ; in Paludina, 315 

 Pleuron, formation of, in Linn/lux, 238 

 Pleuronectes, 22 

 Plexus of muscles in larva of 



appendicvdatus, 148 

 Ploima, 418 

 Pluteus paradoj'iis, 489 

 Podarke, 129 

 Podaxonia, 406, 407, 415, 416; development 



of, 372-385 

 I'oilocoryne, 72 ; development of Medusa of, 



61 



Poison-gland, formation of, in Ayelena, 235 

 Polar bodies, homologies of, 13 

 Polar lobe in egg of /fentalium, first, 326 ; 



second, 326 ; third. 327 ; in the egg of Ilij- 



niKissa, 332 

 Polian vesicle, formation of, in Si/n<i/,tn 



d/i/itata, 538 

 Polychaeta, 128, 161, 205, 211, 285, 372; 



development of, 153-156 

 Polyclada, 102, 117, 164 ; development of, 



103-115 

 Polygonlius, 106, 153, 154, 155, 156, 158, 



161, 163, 164, 165, 166, 293. 294, 299, 



301, 305, 306, 310, 321, 323, 324, 335, 



343, 387, 388 ; development of, 128-153 

 Polygordius appendiculatus, 152 ; later 



larval development of, 144-152 



s lacteus, 144 ; metamorphosis of, 



152 ; later larval development of, 151, 152 

 Polypliinii/x, 193 

 Polypide in Polyzoa, 644 ; formation of, 



in Cyphonautes larva, 394 ; in Polyzoa 



Ectoprocta, 396 

 Polyplacophora, 291 

 Polytrochal larva, definition of, 153 ; of 



Nereis, 156 



Polyzoa, 560, 562, 569, 608, 644, 655 ; de- 

 velopment of, 386-403 

 Polyzoa Ectoprocta, 372, 386, 403, 405, 40H, 



656 ; development of, 387-396 

 Polyzoa Entoprocta, 385, 386, 564, 622 ; de- 

 velopment of, 398-406 

 Pomatoceros, 129, 130, 131, 155 

 J'i',if"j>/i/7tis, Mysis larva of, 215 

 Porania pulwillus, 472 

 Pore-canal,. formation of, in larva of Axtcrin*. 



465 ; in larva of Oji/iivt/i //> f'l-ni/i/is, 489 ; 



in Opliiiirn lii'i'i-iKjiiiiii, 501 

 Pores of shell ofTt'r<'//i'i//n/i/iasepteiit/'ionalis, 



413 

 Porifera, 116, 660 ; compared with Coelen- 



terata, 53 ; development of, 37-52 

 Porocyte, ancestral meaning of, 52 

 Porocytes of Grantia, 43 

 Portuuion, development of, 219, 220 ; young 



and adult stages of contrasted, 22 

 Posterior amniotic fold in embryo of hn<n-i , 



249 ; in embryo of IJoryphum, 261 ; in 



embryo of Odonata, 266 

 Posterior ciliated epaulettes, formation of, 



in larva of Ecliinmt fxculentus, 515 

 Posterior endodermic thickening, formation 



of, in embryo of Iinm/riii, 253 

 Posterior funnel fold in embryo of I.nlii/n, 



357 

 Posterior mantle -groove of 7V/v///v////////if 



septciiti-l'itinlis, 410 



Posterior mesenchyme. formation of, in em- 

 bryo of CyntJ/in /i/i rt if a, 615 

 Posterior mesoderm, formation of. in embi-yo 



of Axi'urix i/ii'i/tduci'/ilitda, 445 

 Posterior sinus, formation of, in /,< //</', ''>>- 

 Posterior vacuolated crest in hirva of <>ji//in- 



thri.i- /1-i.njHix, 488 

 Postero-dorsal arms of cili;ited bund in larva 



of Axtrrinx, 465: in larva of 



esci//i'/iti(x, 509; of larva of 



fragilis, 4!'0 ; of larva of ,sv/v^" <li<i!t,it<i, 



'533 

 Postero-dorsal rods in larva of l-sliimtx 



esculent a*. 509 

 ]'M>tero-lateral arms of ciliated bund of larva 



of Axt'-riii*. lii.'i; of larv:i of Echinocardium 



cordatum, TiL'-J : of l.-n-va of Ophiothrix 



fri/<iilix, 487; of larva of Synapta ihj/itn/it, 



.",:;:', : of New Hn-lan.l Tornaria, 57 ( '> 

 Post ero- lateral i",!-, in larva of i//,/,,',,.' 



fi-ii'tilis, 487 

 Post-larval (h^vdopment of Asteriiut .///,/....-.'. 



17'.'. 180; of Echinus esculentua, 520. 521 

 Post-oral arm of Pacific Tornaria 581 



