HAEJIIOAEHIH HAflT) nPOITECCOMt PErEHEPAHIH Y ENTEROPNEUSTA. 



77 



3to nepewtmeHie AOCTnraeTca bi oHToreHin Tpeiua cnoco6aMH. 



Bt. nepBOMt cjiyqat npoHCxoAnrt nporjeccb OTmenjieHia HepBHaro CTBOJia ott> ociajibHoii 

 3KTOAepMbi. TaKofi npon,eccb Ae.naMHHaii,iH nju£eTi> mtxto, Hanp., bo BpeMH pa3BHTia B. kowa- 

 lewskii no naGjnoAemio EsTCona (Bateson, 85). 



Bo btopomt, cjiyqai mm HMteM'b A'kJio ct. nponeccoMT, norpyaceHia HepBHaro CTBOJia 

 BHyTpb BopoTHHKa, conpoBoacAaromaroca HapacTaeieMT> HaAt hhmi> sKTOAepiabi. 



3totx npon,eccb, cTOJib nanoMHuaiomiH" o6pa30Banie HepBHOH Tpy6bi y Amphioxus, onn- 

 caei PnTTepoMX (Ritter, 94) y Tornaria ct 6eperoBT> Kajn<t>opHin, a TaKate OTqaern, Mop- 

 raHOMT> (Morgan, 92) a ) nsyqaBinnM-b npeBpamede Tornaria (T. agassizii) bo B3pocioe ate- 



BOTHOe. 



Hto KacaeTcn ao TpeTbaro ciyqaa, to Mbi niwEeMi 3Atcb a"bjio ct> THnnqHOH HHBarHHa- 

 nien — t. e. o6pa30BaHieM , b HacToamaro atejio6Ka, Kpaa KOToparo CMbwaiOTca, bt> pe3yjibTaTE 

 qero nojiyqaeTca nepBHaa TpySKa. 



TaKon npon,ecci> onncaHi 6bUT> LIlneHrejieM'b (Spengel, 84, erp. 500). IIpHqeivn> aBTopx 

 HaSjuoAaxb tott> ate caMbig cnoco(fr> o6pa30BaHia BopoTHHKOBaro HepBa KaKi y JiHqHHOK'b, Tatn> 

 n y pereHepnpyromnxTb Bspocjibixi. oco6en. 



HTaifb, nponeccb 33KJiaAKH HepBHon Tpy6Kn BopoTHHKa npn 3M6pioHajibHOM'b pa3BHrin cbo- 

 AHTca kt> TpeMi, hjih Jiyquie Aaate CKa3aTb, AByiwb cnocoSaMi, hjih Tnnaiwb. Y <x>opMT>, pa3Bn- 

 Baromnxca 6"e3T> MeiaMop<i>03a (a hmchho y B. kowalewskii), stotl opraHi o6pa3yeica nyTeitn> 

 AejiaMBHanin, y tex^ ate Enteropneusta, KOTopwe npeiepntBaiorb MeTainop<i>03T>, ohi o6pa- 

 3yeTca nj'TeMT) HHBarnHanin. (CH)Aa Mbi oraeceMTj h BTopon pa3o6paHHbifi Bbime cjyqafi — ciy- 

 qan o6pa30Bama nepBHofi Tpyonn nocpeACTBOMi. norpyaceHia HepBHOH njiacTHHKH hoa^ Koaty). 



BnpoqeMT), n y Balanoglossus kowalewskii TOJibKO bi cpeAHen qacTH HepBBOH Tpy6KH 

 BopoTHHKa Bateson Ha6jnoAajn> AeJiaMHHaiiiK), Ha nepeAeeM-L ate n 3aAHeMt KOHnaxT> HepBa 

 BopoTHHKa Ha6jiK>AaeTca lnnnqHaa HHBarHHania, hoaoSho Tony, itanx 3to HMEerb mtxto y bcbxx 

 Tornaria, npeBpamaromnxca bo B3pocJioe atHBOTHoe. 



TaKHMT> o6pa30\i-b caMbiM^ THnnqHbiMT. cnocoSoiwb o6pa30Bama nepBHofl ipy6KH npn 

 3M6pioHajibHOMT) pa3BHTin Enteropneusta HyatHo cqniaTb nHBarHHaniw hjh BHAOH3MBHeHie ea — 

 npouecc^ norpyaceHia HepBHOH njiacTHBKH BHyTpb h nocji-KAyiomee 3aMbiKaHie ea bt, Tpy6Ky. 



Taicb HMeHHo h o6pa3yeTca 3rorb opram npn perenepaniH. 



HTaKi, noABOAa HTorn, Mbi npHXOAnwb Kh Tomy 3aKJiK>qeHiK), qw MeatAy perenepaTHBHbiMi 

 h 3M6pioHa^bHbiMi opranorene3awn Ha6jK>AaeTca no^noe npHannnia^bHoe cooTBBTCTBie. 



1) Morgan (92) CTp. 95. «A careful examination 

 shows that here a plate of ectoderm is sinking below 

 the surface, and at the same time the collar is rolling 



over the invaginating plate of ectoderm from the two 

 sides». 



