iv PRONEPHEOS 225 



the archinephric duct, which thus owes its origin to the fusion 



me 



nc. 



FIG. 123. Development of pronephros of Hypogeophis as seen in transverse sections. 

 (After Brauer, 1902.) 



A, .-mhryn with _'_' s.^m.Mits ; H, with _". segments; C, with 44 sr.-mrnts. A, dorsal aorta ; end, 

 endoderm ; gl, glomonilus : /. ///, lateral mesodonn ; //<, niyocoele ; my, myotome ; N, notochord ; nc, 

 nephrocoele ; ns, m-phrostonie : y.c, peritoneal canal; pn, pronephric t-ulmle ; .t.c, spinal cord; sd t 

 selcrotome ; spl<\ 



together of the outer ends of the tubule rudiments belonging to 

 segments IV, V, and VI. 



VOL. n Q 



