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TABLE VI. 



Systematic Survey of the principal organs of the ideal Primitive Vertebrate, 

 the hypothetical parent-form of Vertebrates, and of their development 

 from the germ-layers. 



I. 



Skin-layer 

 (Animal germ-layer, 



Baer). 

 Lamina dermalis, H. 



Exoderma. 



Skin-sensory layer 



(Skin-stratum, Baer), 



or 



Sensory layer. 

 Lamina neurodennalis, H. 



Skin-fibrous layer 

 (Flesh-stratum, Baer), 



Flesh-layer. 

 Lamina inodennalis, H. 



1. Outer skin (Epidtrmit\ A 



simple cell-covering of the 

 outer surface. 



2. Spinal tube (Tubus medul- 



laris) (with the organs of 

 sense : the nose, eyes, organs 

 of taring). 



3. Primitive Kidneys (Protone- 



phra) (a. pair of simple ducts, 

 primitive kidney ducts). 



4. True skin (Corium) (Cutis and 



iubcutis'). 



5. Muscles of the trunk (dorsal 



and ventral muscles). 



6. Notochord(aorda<io?-.aZi). 



7. Kxoccelar, or Parietal Ca-loni- 



epithelinm (the inner roll- 

 covering of the body-wall). 



8. Male sexual glands (fates) 



Coeloma, or Body-cavity. A space between the body-wall and the 

 intestinal wall, between the exoderm and the entoderm, filled with lymph 

 (colourless blood). 



cell-covering of the intestinal 

 (Mucous stratum, Baer), tube). 



or ) 15 Intestinal glandular epithe- 



MUCOUS layer lium 0>*er-cells and other 



Lamina W a*rSi, S. \ inte8tinal * landaUr <* lls >- 



VOL. I. 



