BLOND AND WHITE RING-DOVES CROSSED WITH MOURNING-DOVES, ETC. 139 



Further breeding of the three sons and tlie daughter from the first cross was 

 carried out as follows: 



Male D 1 was mated during two years with a blond ring (table 121), and during 

 another two years with a white ring (table 122). It might seem from a comparison 

 of the two records that, although there is much infertility throughout, this male was 

 more fertile with one of the parent species (alba) than with the other (Hsoria). 

 The known value of age in relation to fertility, and the lack of this data for the 

 female alba, preclude such a conclusion. It is, however, of considerable interest to 

 note that the offspring of Dl and the weaker" of these two species (alba) are nearly 

 all females. Only 1 male was found among the 9 young whose sex was ascertained. 

 Two of the young from the mating with the blond ring are shown in pis. 37 and 

 38; one from the mating with alba in pi. 38. 



The second male {alba-risoria-turtur hybrid G) was nearly fully fertile with 

 risoria, development failing only in the first and last 2 eggs of the first season, 

 and falling a little short only in the second and third of the 10 eggs of the following 

 season. But when mated to his daughter 5 of their 6 eggs failed to hatch. When a 

 hybrid carrying still a different species was offered very little development was 

 possible, and this was found in the first pair of eggs of the season (table 123). 



Two of the young of this trispecific x risoria cross were tested for fertility. 

 These were both males, 1 being light (B 2) and 1 dark (C 2) in color. B 2 mated 

 to a pure blond produced (July) 2 eggs unable to hatch, followed by a pair (August) 

 that produced 2 young that lived at least till they had adult plumage. The first of 

 these was a male with the color of a blond ring-dove; the second was similar, but 

 more clearly showed the reddish color of turtur, her parental grandmother. The 

 result of the mating of C ^ with a humilis-risoria hybrid, the entrance of a fourth 

 species into this cross, is given in table 124. The two offspring are both females 

 and have the composition: tV alba, W risoria, tV turtur, jw humilis. 



The third (Jl) of the tested brothers — -from the original cross with T. turtur — 

 was mated with the same blond ring previously mated and found fairly fertile 

 with another brother (G). Fertility was here much restricted, as may be seen by 

 reference to the bottom row of table 123. 



We have thus presented the record of 3 trispecific hybrid brothers back-crossed 

 to a risoria female. One of the sisters {D 2), a sister from the same clutch as D 1, 

 was back-crossed to an alba male, and the data are presented in table 125. Three 

 different males were tested with this female (D2) , and the several records make 

 clear the low degree of fertility of this female trispecific hybrid. With hybrids 

 related to her the infertility was absolute. With pure risoria she was, like her 3 

 brothers, at least partially fertile. 



Tabi.k 119. 

 cf alba-ris. X ris.-alba hyb. (D 2) ; 8/27/97; brown (lighter color than mate). 

 9 T. turtur (B 1); 4/29/99; alive July 1903; (darker than mate). 

 A. 3/22/00; soft shell. 9 F 1. 5/30; very light, dead 9/19/04. 



F 2. 0/1; no development. 



B 1. 3/30; thin shell; removed. cTG. 7/1; color dark as D 1. 



B 2. 4/1; thin shell; broken. H 1. 8/1 ; no development. 



C 1. 4/9; no record. H 2. 8/3; died autumn 1900. 



C 2. 4/11; no record. j 4/23/OI; thin shell. 



o ^ ^/oo' f"^^.''' ",'■■"' °r f '? 'Hl^^^^- ^ J 1- 4/30; dark color, killed 2/4/0.5. 



9 D 2. 4/22 ; light ; pale centers to feathers. J 2. 5/2 ; no development. 



' P 9- f/9«= r^ "''V •^rV^''/""- K 1. 7/9; no development. 



E 2. 5/26 ; from perch, broken. K 2. 7/1 1 ; no development. (DD 4. C) 



' See Cliapter XV. 



