564 C. C. Guthrie 



ing about 650 gms. each. One black and one white pullet were 

 saved for controls. All did well for some time after the opera- 

 tions but during the winter, before the laying season began, their 

 condition became extremely poor owing largely to being kept in 

 inappropriate quarters. They lived until the following Septem- 

 ber but no eggs were laid, even by the controls. During my 

 absence after this date, all but one of the hens were lost, including 

 the controls. The remaining operated hen was killed about 

 October 15, and preserved. 



In size and external appearance the hen that was killed seemed 

 normal. Macroscopically, the ovary appeared normal in size, 

 location and in its relations to the surrounding structures. It 

 was many times larger than when transplanted. At the time 

 of the operation the Graafian follicles did not exceed i mm. in 

 diameter while postmortem they ranged from 5 to 10 mm. No 

 corpora lutea were observed. Histologically, the ovary appeared 

 normal. The hen was found to be affected with tuberculosis and 

 the ovary was involved, as evidenced by the discovery of a few 

 of the bacilli in the stroma. 



On August 25, 1906, another series of pullets of the same 

 strains^ were similarly operated upon, controls being saved as 

 before. They weighed about 750 gms. each, the white ones 

 being slightly the heavier. All did well after the operation. 

 About August 31, they were sent to Columbia, Mo., where they 

 were kept in a small poultry yard until January 21, 1907, when 

 they were shipped to this laboratory.^ They have since been 

 kept in individual pens. The roosters have been kept in small 

 slightly closed cages except for the time they have been placed in 

 the pens to tread the hens. Great care has been exercised to 

 keep the records correct in all respects. 



SUMMARY OF RESULTS 



No marked differences in egg production were found between 

 the control and operated hens, nor in the fertility of the eggs. 



' All of the chickens of the single comb black and white leghorns used to date, including the rooster, 

 have been purchased of E. G. Wyckoff, Ithaca, N. Y. 

 ■* Excepting W^, as per addenda to table. 



