llll. ORGANS UK I II 



325 



umc 



Fig. 185. -Cross section through the anterior part of the trunk of an embryo of Scyllium, aft* 

 BALFOUR. 



Between the dorsal and ventral walls of the body, where the attachment of the talk of the yolk- 

 sac is cut, there is stretched a broad mesentery which contains numerous ceils and complete)/ 

 divides the body-cavity into a right u ..Klenura (<fu), lying in the 



mesentery, is twice cut through ; dorsal ly it gives rise to the fundiinient of the pancreas 

 (jxin), ventrally to that of the liver (/<;>.(/). Further, the pla- ne .hu-t 



(tone) emerges from the duodenum is to be seen, ip.c, Neural tube (spinal co:> 

 ganglion of ixwterior root ; or, anterior root ; tin, do really directed nerve springing from the 

 posterior root ; mp, musc'e-plate ; -;;>/'-, ]>art of muscle-plate already converted into muscles ; 

 mp.i. i \vliich gives rise to the muscles of the limbs ; nl, nervus lateralis ; 



no, aorta ; c/t, chorda ; sy.y, sympathftic gan.qliou ; ca.v, cardinal vein ; sp.n, spin..: 

 ad. sowir.ental duct (duct of primitive kidney) ; if, segmental tube (pronepluic tubule). 



