( 3§7 ) 

 TABLE XLII. 



Systematic Survey of those Primitive Organs which must probably be 

 regarded as homologous in "Worms, Articulated Animals, Soft-bodied 

 Animals, and Vertebrates. 198 



"Worms ^ 

 (Vermes). 



Articulated 



Animals 

 (Arthropoda). 



Soft-bodied 

 Animals 

 (Mollusca). 



Vertebrates 

 (Vertebrate). 



I. Products of the Differentiation of the Skin-sensory Layer. 



1. Oater skin 



1. Chitinous skin 



1. Outer skin 



1. Outer skin 



(Epidermis) 



(Hypodermis) 



(Epidermis) 



(Epidermis) 



1. Brain (upper throat- 



2. Brain (upper throat- 



2. Brain (upper throat- 



2. Medullary tube (an- 



ganglia) 



ganglia) 



ganglia) 



terior part) 



2. Excretory organs 



3. Shell-glands of the 



3. Rudimentary kid- 



3. Primitive kidney- 



(water - vessels, 



Crustacean 



neys (Primitive 



ducts (Proture- 



segmental organs) 



(trachea of the 



kidneys) 



teres) and seg- 





Tracheata ?) 





mental organs 



II. Products of the Differentiation of the Shin-fibrous Layer. 



4. Leather-skin 



4. Leather-skin 



4. Leather-skin 



4. Leather-skin 



(Corium) 



(Rudiment) 



(Corium) 



(Corium} 



(together with the 





(together with the 



(together with the 



circular muscle- 





muscles of the 



muscular layer of 



pouch ?) 





skin ?) 



the skin ?) 



5. Longitudinal 



5. Trunk-muscles 



5. Inner trunk-muscles 



5. Side trunk-muscles 



muscle-pouch 









6. Exocoelar innermost 



6. Exocoelar innermost 



6. Exocoelar parietal 



6. Exocoelar parietal 



cell-layer of the 



cell-layer of the 



epithelium of the 



epithelium of the 



body-wall (also 



body- wall (also 



ccelom (also male 



ccelom (also male 



male germ-plate?) 



male germ-plate?) 



germ- plate?) 



germ-plate ?) 



III. Producti 



of the Differentiation of the Intestinal-fibrous Layer. 



7. Body-cavity 



7. Body-cavity 



7. Body-cavity 



7. Pleuro-peritoneal 



(Cceloma) 



(Cceloma) 



(Cceloma) 



cavity 



8. Endoccelar outer- 



8. Endoccelar outer- 



8. Endocoelar visceral 



8. Endoccelar visceral 



most cell-layer 



most cell-layer 



epithelium of the 



epithelium of the 



of the intestinal 



of the intestinal 



ccelom (together 



ccelom (together 



wall (together 



wall (together 



with the female 



with the female 



with the female 



with the female 



germ-plate ?) 



germ-plate ?) 



germ-plate ?) 



germ-plate ?) 







9. Dorsal vessel 



9. Heart 



9. Chamber of the 

 heart (and main 

 artery) 

 10. 



9. Aorta (primordial) 



10. Ventral vessel 



10. 



10. Heart (and gill- 



artery) 



11. Intestinal wall (ex- 



11. Intestinal wall (ex- 



11. Intestinal wall (ex- 



11. Intestinal wall (ex- 



cept the epithe- 



cept the epithe- 



cept the epithe- 



cept the epithe- 



lium) 



lium) 



Uum) 



lium) 



IV. Products of the Differentiation of the Intestinal- glandular Layer. 



12. Intestinal epithe 

 Hum 



12. Intestinal epithe- 

 lium 



12. Intestinal epithe- 

 lium 



12. Intestinal epithe* 

 Hum 



