mi: ORG LN8 OF UN: MIMIM - \ 1:1:. 



373 



of figure I'll* exhibit tlii- rondition. Fii'im- //' ftbowi i IM- 

 \vhere the ventral \\all t' the me.-onephric iiiekeried ini,, 



a ridge (at'/) by an increase of the epithelial cells; upon a cross 

 -ft ion (.1) M.ade farther forward tin- thickened j-art has become 

 d.Marhrd BA a o ml 



//), wliicli -ul 

 (jurntly becomes -till 



inorr isi.latr.l and ac- 



'jiiii'f- a cavity >t its 



i>\vn. Tin- mi:lition 



i-y clf;irly 



t lie a ] pea ra lice- 

 \vliirh tin- 



tit nis tliroii^h embryo 

 liians (fig. -_'()9) 



Fig. 212. Two sections to show the union of the solid terminal 

 A,OCOTding to the part of the Mullerian duct with the me ,nephric duct in 



the Chick, sj it AXD SEIX;U 



ObserV&tiODS of SKDG- In A tin- tcnniiril i..u: is 8till ijuiU; iliMiiu-tlv 



WICK, therefore, the 



anterior end of the 



Miillcrian dnct would 



lie drrived t'roin the jn-inn-jlir(, hut the po-terior enl hy a splitting 



off of cells t'roin the uii-x'iM-plirii- duct. Thus an a^neinent with 



the niiditi"ns in the n<n-.Miinioi : Vrrti-hratc- \\.uM he estahlished. 



Fig. 213. Cross sections through the Wolffian and Miillerian ducts of two human embryos, after 

 N it 



A \ tVni.il'- rinlir\ .! D n.. 

 B, A male embryo '1. inni. \\\. 

 H'.y., W.ilttian <hu-t ; .M.-.i.. <-n.l ..f tin- Mn!'- lit 



It still deserves to be especially inentiom-d that in human einhi-\d- 

 also the Miillerian dud- (fig. 213 .! and I> M.g.) during their 

 development have their po-ierioj- ,-nd- t'n-. <1 for a short di.-t.-mce with 

 the nu'-onephrie duct < II ".;/.>. XA;KI.. to \\hom \v- are in-lehted t'.ir 

 this line observation, e.xpiv - him-ell'. it i- t r . splitting 



