HABJIIO^EHIH HA^T. HPOqECCOMT) PErEHEPAIIIH y ENTEROPNEUSTA. G7 



eajibHOMx pa3BHTie Enteropneusta npnHaAJieacarL EaTCOHy (Bateson, 84, 85, 86, 87) h 

 MopraHy (Morgan, 92, 94). 



PaGoTbi sthxt. aBTopoBi> BbificHHJiH ecna a He ct> acejiaeMoa, to Bee ne ct AocTaroHHoii 

 nojiHOTOH xoax pa3BHTifl no^TH BcfexTh opraaoBT>. 



Ran ocBtuieuia a-EKOTopbix-b BonpocoBb mb-e Ka3ajiocb ire jhuihhmx BpeftieHaiun o6pa- 

 maTbca 3a cupaBKaiua kt> toh JiaTepaTypi, KOTopan 3a nocjiEAnee Bpema naKounjiacb othoch- 

 TCJibHO npoueccoBi noaicoBaHia, a Aaace OMopionajibiiaro pa3Baria Pterobmnchia — rpynnbi, 

 necoMH-BOHO, oieHb 6jih3ko CToaui,eH kt> Enteropneusta. 



Bt> AaibHEHiueMt H3Jj0JKeHin a 6"yAy pa3(5npaTb OTHOcauiiaca cwAa MaTepiajn> ajih aaac- 

 Aaro opraHa OTAfabao. 



CerMGHTan;ia. 

 OGpaTHM-b npe>KAe Bcero Biinmauie aa to, icaK-b nponcxoAnrt ceraieainpoBanie pereaepaTa. 



Mbl BHA'BJIH, ^TO eCJIH aiMByTHpOBaTb JKHBOTHOe BT> 06jiaCTH XBOCTOBOrO OTA'Bia, TO 3T0T'b 



xboctoboh yaacTOKi B03CTaH0BJifierB nepeAHie cermeaTbi bx TaKOMT> nopaAK'fc: cnepBa o6pa- 

 3yeTca nepeAaia I-a cerMeart (xo6orb), 3aTBM^ aa rpaanafi MeacAy I a III — 3aKJiaAbiBaerca 

 11-fi cenuearb (bopotbhki). (Phc. 2-h Ha CTp. 10). 



IloAoSabiH ace bophaoktb noaBJieaia 2-ro cerwea-ra (BopoTHHKa) HaSjaoAaeTca a npn amSpio- 

 HajbuoMT, pa3BHTia — npn topjinpoBaHin, nanp. 3apoAbima Balanoglossus howalewshii Ag. 



Flo HaSjuoAemaMT, EsTCoaa (Bateson 84, PI. XIII, fig. 11 — 14, CTp. 135) aecerMea- 

 TnpoBaaabiH Baaaaji-t 3apoAbinn> A'k-nnTca aepeTaacKoa aa Ana cemeaTa — I-fi n Ill-n, t. e. 

 xoSorb n TyjiOBame, n TOJbKo aa cafsAywui.HX'b CTaAiax-b 3aKiaAbiBaeTca II-a, BopoTanKOBaa 

 MeTainepa. Tott> ace nopnAOicb aoaBJieflia ceraenTOB-b Ha6jiioAaeTca n npn npoueccE noHKOBaaia 

 y Pterobmnchia Kaicb y Cephalodiscus, 'rant h y Rhabdopleura. 



HapyacHBie hokpobli. 



Hapyacawe BOKpoBbi pereaepnpywai.HX'L yqacTKOBi, Ptychodera o6pa3ytOTca, kukt. 3to 

 jierKO BHABTb, n3yaaa apnBeAeaHbie pncyHKa, nyTeiut pa3pacTania 3KT0AepMbi ocTaBuinxca 

 qacTea acnBOTHaro, BoporanKa mh TyjiOBHin,a — cworpa no cnocooy aMiryraiun. CyoxsnaTe- 

 Jiiajibaaa HepBaaa BbicTHJina kohch o6pa3yerca bt» pereHepapyioiiiHX'L yqacTKaxx 3KTOAepMbi 

 nyxeMi AH^'sepeHnnpoBaHia BOJiOKHacraro BeajecTBa H3T. uaTeBnAHbixij otpoctkobtj 3KT0Aep- 

 MajbHbixt kjtetokt>, t. e. TaKn»n> ace cnocoftonn, KaKHivn. noAKoacubin nepBHOBOJioKaacTbia 

 cjiofi o6pa3yeTcn y sapoAbimea Balanoglossus lwwalewsldi no iiaojnoAeiiiajrb EsTCoaa (Bate- 

 son, 85). 



DjeJiOM-B. 



Ilpn pereHepaaja Ptychodera — aejowi, BcerAa o6pa3yeTca, KaicL mbi bhabjih, n3x 3,ic- 

 mghtobi cTapbixx y'lacTKOBTD u,ejioMn i iecKOH nojiocTa — n,ejioTeJiia n uejieaxnuibi. 



