204 



tNHERITANCE, FERTILITY, AND SEX IN PIGEONS. 



The results of two such reciprocal crosses incubated simultaneously, and with 

 the eggs of the crossed birds interchanged with uncrossed birds for incubation 

 purposes, may be found in table 185. It is there indicated that the sperm of the 

 male tumbler added 7 to 24 hours to the incubation period. 



Eggs from a further cross between a male ring-dove and a female homei- were 

 incubated simultaneously with eggs from three pairs of common pigeons. The 

 result, as seen in table 186, indicated a shortening of the period by about 8 to 26 

 hours as a result of fertilization by the ring-dove male. 



I have studied the incubation period of the eggs of the wild passenger-pigeon 

 {Ectopistes vngratorh(s) and have also obtained data on the length of this period 



-Iiinilinlinn time of a' cniiin 



9 ring-dove (D ^')- 



Hatched. 



4 to 6 p.m. May .3, 1S90. 



5 to 9 a.m. May 5, 1S9(J. 



4 to 6 p.m. May 23 



Si- SO" a.m. May 25 



3.m. July 1. . . 

 1 . m . . July 3 . 



S"- SO" p.m. July 20. 



5''30'" to Gp.m. Aug. 2. 

 7 to 9 a.m. Aug. 4 



4 to 5 p.m. Aug. 24 



8 to 9 a.m. Aug 2(i 



S"" 50™ p.m. Sept. 11 



4 to 4'' 45™ p.m. Oct. 11. 



S"- 47™ a.m. Oct. 13. 



No development. 

 No development. 

 11 to 12 a.m. June 

 Developed; did not liatih. 

 No development. 

 No development. 

 No development. 

 No development. 



No development ; Re 



No development. 



Developed to about a week. 



No development. 



No development. 



No development. 



No development. 



No development. 



No development. 



15 das. 18 to 19 hrs. 



. (lung for 2d egg). 



Developed to one 

 No development. 



4 to 6 p.m. Dee. 20 Before 6 a.m. Ja 



g*" 20™ a.m. Dec. 22 | No developnicn 



5'' 05™ p.m. Jan. 23 ' No developmi-n 



lO"" 05™ Jan. 25, 1897 j Before G a.m. F 



5'' 04™ p.m. Feb. 20 ' Developed for v 



9'' 28™ a.m... 



4 to 6 p.m. Apr. 17 . . 

 7'' 50™ a.m. Apr. 19.. 

 5'' 53™ p.m. May 16. 

 a.m. May IS. 



6'' 21™ p.m. June 20. 

 Sh 53™ a.m. June 22. 



Developed but Kiliccl. 



5 to 6 a.m. Apr. 4 



No development. 



Developed but stopped. 

 Developed but stopped. 

 No development. 



No development. 

 Developed, failed. 

 Developed, failed. 

 No development. 



14 das. 18 to 20 hrs. 



IS das. 12 to 13 hrs. 



5 to 6 p.m. July 12 , 5 to 6 a.m. July 2! 



7 to 9 a.m. July 14 5 to 6 a.m. July 2i 



4 to 7 p.m. Aug. 22 | No development. 



Premature ] Not tested. 



IS das. U to 13 hrs. 

 14 das. 20 to 23 hrs. 



: 41 eggs; raised 4 ma 



hatched; 16 fertilized. 



