14 



INHERITANCE, FERTILITY, AND SEX IN PIGEONS. 



ceding lists) , and this latter number is followed by the number of the table or tables 

 in which this record, or the chief part of it, may be found. 



An additional list of all ^ "individual matings which tested absolutely infertile" 

 is given herewith. From this list it is evident that the primary cross of widely 

 separated forms is itself less and less fertile in proportion to the degree of the sepa- 

 ration of the forms. Nearly all of these completely infertile matings comprised 

 forms of family or of subfamily distinction. Few matings of forms only specifically 

 or genericall}^ different proved whollj^ infertile, although the total number of such 

 matings made was many times the number of family and subfamily matings. 



Those who are not acquainted with the classification of Columbse will find the 

 diagram given herewith (as arranged by the author, in part after Salvadori, 

 1893) of help in obtaining a general idea of this subject. Later reference to this 

 schematic arrangement of the various groups of pigeons will enable the reader to 

 learn or to verify the degree of separation of the members of the more distantly 

 related crosses. 



Classificalion of Cohwiba'. 

 Order Columbse. Suborders j 



Order COLUMB^ 

 Suborder Columhae 



1. Columbse. 



2. Didi (extinct). 



Didi 



Family 1 Treronidse, 



4 Gouridse 



2 Columbidse 



3 Peristeridae 

 Didunculidse 



Fam. Peristeridae 



A few additional matings of thi.s sort are fully presented later in the breeding records 



