In Triturus newts, half of all offspring die. Scientists have long known that one part of their DNA—chromosome 1—exists in two different versions. Animals need both versions to survive. During ...

IN the course of investigations on tissue homotrans-plantation in the North American species, Triturus viridescens, a number of experiments were made. Regeneration blastemas (from the tail) were ...

During experiments designed for a purpose remote from the subject of this communication, we had tried to remove from a young neurula of Triturus tæniatus the fore part of the presumptive area of the ...

This media is in the public domain (free of copyright restrictions). You can copy, modify, and distribute this work without contacting the Smithsonian. For more information, visit the Smithsonian's ...