SPINAL NERVES IN VERTEBRATES 195 



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mark. 2. Gehirn. Arch. Mikr. Anat., Bd. 73. 



1913 Die zentralen Sinnesorgane bei Petromyzon. Arch. Mikr. 



Anat., Bd. 83. 

 VoGT, C. UND Yung, E. 1894 Lehrbuch der praktischen vergleichenden Anat- 

 omic. Braunschweig. 

 WiEDERSHEiM, R. 1880 Die spinalartigen Nerven von Ammocoetes und Petro- 

 myzon. Zool. Anz. 



1880 Das Gehirn von Ammocoetes und Petromyzon planeri. Jena. 



Zeitschr., Bd. 14. 

 WiJHE, J. W. VAN 1882 Ueber die Mesodermsegmente und die Entwicklung 



der Nerven des Selachierkopfes. Verhandl. d. koninkl. Akad. d. 



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us-Ruckenmarkes. Biol. Centralbl., Bd. 27. 

 WoRTHiNGTON, JuLiA 1905 The descriptive anatomy of the brain and cranial 



nerves of Bdellstoma dombeyi. Quart. Jour. Micr. Sci. 

 Wright, R. R. 1884 On the nervous system and sense organs of Amiurus. 



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 Wyman, J. 1853 Anatomy of the nervous system of Rana pipiens. Smiths. 



Contrib. to Knowledge, vol. 5. 



EXPLANATION OF THE FIGURES 



All figures are from drawings of graphic reconstructions, transverse sections or 

 dissections. The graphic reconstructions were made after a method given in 

 an earlier publication (Quart. Jour. Micro. Sci., vol. 59, p. 352-3, 1913). The 

 outlines for the transverse sections were drawn with the aid of an Edinger-Leitz 

 projection apparatus. In general the motor nerves are represented as solid 

 black areas, the sensory nerves, spinal ganglia, and veno-lymphatics are drawn 

 in outline. The central nervous system is cross-barred. Arteries are finely 

 stippled on two sides and the veins are filled in with circular lines. Cartilage is 

 coarsely stippled and muscles are shown as fine lines longitudinally or as fine 

 dots transversely. Mucous sacs are portrayed as a mass of small circles and 

 nerve cells may be represented similarly or they may be filled in with solid black. 

 In a number of instances the dorsal and ventral borders of the myotomes are 

 designated by a dotted line, consisting of alternate long and short lines. A-B 

 in the reconstruction drawings denotes the base or projection line from which 

 all structures in the reconstructional drawings were plotted. In the first re- 

 constructional drawing of every reconstruction it represented a horizontal line 

 passing along the ventral surface of the notochord. When a given structure 

 assumes a dotted outline upon arriving at a second structure or organ it signi- 

 fies that the first structure passes deeper to or within the second structure. 



