R. H. Thomas 283 



traced to their source : also that the moult habit remained Swinhoe 

 in the fourth generation, and that the leg colour was sexual hybrid and 

 racial hybrid throughout the four generations. 



IV. That the connection between the two species crossed can be 

 traced by the eight month transition plumage of the Silver J" and the 

 adult Swinhoe $ plumage. 



V. That a mutation appeared in F^ which has been distinctly 

 traced to colour and pattern-transference and which was capable of 

 hereditary transmission (Plate XXII, fig. 16). 



APPENDIX A. 



Here follow a detailed examination and comparison of the several 

 plumage areas exhibited in the fi-amed feathers, of which plates are 

 printed. 



Feathers were extracted and set on cardboard from the tail, wing, 

 breast, flank, thigh and crest, taken from the same locality in each area, 

 of the following birds. The method emj^loyed was to copy the ring 

 inscription on to an envelope then extract the feathers and place them 

 within. 



Parent Species. 



Gennaeus nycthemerus^, "B" $, Silver J, parent of i^, . 

 Gennaeus swinhoei, "A" $ , Swinhoe ? , female of parent of F^. 

 Gennaeus nycthenierus, "Z" $, mottled and vermiculated type of "5." 

 Gennaeus nycthenierus, " B" <^ , young male of eight months old in iii-st 

 plumage. 



3. F,. "BA" ? ?. 



2. F^. "BE A" ? ?. 



6. F,. "BBS A" ? ?. 



5. F,. {F„ inter se "BBBA") ? ?. 



First examination giving pattern and colour in detail. 



CREST. (Plate XXII.) 

 Parent Species. 



"B," $ . Crest : blue-black, feathers slender, barbs long, structure 

 degenerate. 



Anterior : length 1^ inches. 



Posterior: length 1| inches. Plate XXII, fig. 1. 



"B" type of Gennaeus nijcthemerus ? was used throughout the experiment. 



