COLLABORATOR OF DARWIN 10 



born well clothed with down. The application 

 of these facts and countless similar ones is of 

 no concern to us here ; they are cited merely 

 to show the extreme exactness of Tegetmeier's 

 observation, and the seemingly insignificant trifles 

 he noticed while engaged in breeding birds. The 

 information contained in the following passage 

 from Darwin's " Variation " is an example of this 

 trait : " Mr. Tegetmeier informs me that when 

 distinct breeds are crossed, fowls are frequently 

 produced with feathers marked or pencilled by 

 narrow, transverse lines of a darker colour." This 

 would be of interest to Darwin as indicating the 

 tendency to revert to the original parent form of 

 fowl. Tegetmeier was able to tell him also that 

 although there is so great a variety of pigeons, 

 none is known to possess pencilled or spangled 

 feathers — a fact of equal interest to his 

 correspondent, inasmuch as neither the wild 

 rock pigeon — the parent form — nor any closely 

 allied species has such feathers. 



The two naturalists worked together in many 

 breeding experiments. Darwin, for instance, 

 having tried the crossing of several varieties of 

 domestic pigeon and found their progeny fertile, 

 appealed to Tegetmeier to repeat the experiment 

 independently and inform him of the result. 

 So with fowls : when Darwin had made his own 

 breeding experiment with a Spanish cock and a 

 Silk hen, he asked Tegetmeier to repeat it. He 



