POLYEMBRYONIC DEVELOPMENT IN TATUSIA 
NOVEMCINCTA.! 
J. T. PATTERSON 
THIRTY-FIVE TEXT FIGURES AND ELEVEN PLATES 
CONTENTS 
PPO LUPE esti cen eee pee Pee S88! 8s ayy ud 'n ee « ele ree ee ee 560 
MIGHIMNOOES 5 5 joe.a bce b cake aR CLs 6 ten bi ae Bene ee me ot” 561 
TL, “Weeliniamio Res; oS he, teen es Sa Sats alee ts oe ee MEE re 2 561 
Pe eT WmasGlNeCUNIN GALUY SUAGES fon ko. ice a cas ce oe ees sp bon Ac cae eee 561 
Nigiies Gin Lomevxolinnyia niin OSS, Ae Be Seinen a RS Taki |) 563 
Loo, CCCIVEISE AST TES OOS On hey ib SA ol ne Covet etl. S 563 
men ertl ea ale mn OTA beens oiler SiN ext. «ened sw a d-0a ce bod vood ben Ge 566 
BECO OMIeHE Orso eT DIAS UOEY SO iu. 6 ew ca ie et te es son sae a oes side 2 a 569 
Heeiic mInNOdermre OIASUOCYSL <1. c dares Gs es eae ov eenen dhad ORs 569 
Ds Toes CUCIA ATE SHAS ce Lae en Se ed MMe eer) oe 574 
Ep CMe teh Me OLAShOCV Ete 8e a okie cles, «4s a+ iw oto eleeid = SEER eS 
Houmananuor Re ectOouermic VEsICle. 25.55... ...-<-. sce. s0 sal vols tees eeeee 587 
Origin of the extraembryonic mesoderm or mesothelium................ Seba? DOS 
UENO WAM OL Mer TOMMNS! 2. ne. selec 5 cs oats ees slave es eee Oe 
CEES ELE T0 atv 3) 0)00 Ss A a re en re curren et eee 598 
Oey ehp DEH COMMAT VAM Sas. or 1, pads, wise) as ates «eco sts aims od Sr odd ea 603 
Extension of the secondary buds and organization of the embryos........... 610 
implantation oO: Ovum and plAcentatlion:.......2........6.. 0004s seem nee ae 617 
ee tere IS CIS SLONIN No te AIRED. ck Pt ws sa we ke et 625 
uivheorlesotppolyemlomyvomyee ernie os iio sols «ose slats oeiehye op eee eee 625 
Pee ORY ON DOlVOMUlAr TONAGIES!, 2c. visd.. 0+ + +0 s.. ame a akin eee eS 625 
DamUReOny Om LAST ObOULy iva. ssc... + ¢ s+ ses anh stew oa ee 629 
Colihconyeolnome Chm eens ee tka. «aS LecateaG eve os A ae eee 631 
ZROrIE eat poLembryvany ine Dasypodidac.... 142 +).4<i4044 beatae eee 636 
3. Polyembryony and duplicate twins and double monsters ............... 641 
PR HENMAN ONIN (RUG BE Rae Te ca i secs = «1a. 2s a's) s wt alo oe po Ca eee 643 
SITU? 10 eee Sa ene cle, th SS RS a Re ag td ae oer 645 
[SSI CVOTNERELIRV RAN Thy eel A i Coo 5 A re mR ES ey A ne TaN, 648 
! Contributions from the Zoological Laboratory of the University of Texas. 
Noses 
5a9 
