342 Papers from the Department of Marine Biology. 



von Berenberg-Gossler; and sympathetic ganglia in the loggerhead 

 turtle, Jordan) ; and to their apparent primary (urodeles) or secondary 

 (anurans and other vertebrates) derivation from the splanchnic layer 

 of the lateral mesoderm are incidental to their original location with 

 respect to the embryonic area and the vascularizing mesoblast of the 

 blastoderm, and to their amoeboid capacity. Since the primordial 

 germ-cells are genetically directly related to neither of the secondary 

 germ-layers, their origin in either (entoderm or mesoderm) has no 

 fundamental significance. Since they are capable of amosboid activity, 

 and may become included in blood-vessels, they may migrate any- 

 where, and so occur in any location, from where they may subsequently 

 migrate again to the more direct germinal path, or perhaps disintegrate. 

 The fact of fundamental significance with respect to the primordial 

 germ-cells is their original extra-regional distribution and their direct 

 genetic independence of the soma-cells. 



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