Ovulation in the Domestic Fowl 161 



As has been noted elsewhere (18), Bastian and Zarrow and this author are 

 in agreement in assigning to photoperiod the basic role of timing the appear- 

 ance and termination of the "open" period of low thresholds in the neural 

 component of the OIH (or LH) release mechanism. But while Bastian and 

 Zarrow conceive of an immediate and constant functional relationship 

 between the appearance of the open period and OIH release, much evidence 

 reviewed in this paper impresses the conviction that timing of the specific 

 nervous activity resulting in OIH release is conditioned largely by the 

 ovarian hormones and the order of follicular maturation. 



REFERENCES 



1. AssENMACHER, I., Arch. Anat. microsc. et Morphol. exp. 47, 447-572, 1958. 



2. Bastian, J. W. and M. X. Zarrow, Pioc. Soc. Exp. Biol, and Med. 79, 249-252, 1952. 



3. Bastian, J. W. and M. X. Zarrow, Poid. Sci. 34, 776-788, 1955. 



4. Bates, R. W., E. L. Lahr and O. Riddle, Ainer. J. Physiol. Ill, 361-368, 1935. 



5. Benoit, J. and I. Assenmacher, Arch. Anat. microsc. et Morphol. exp. 42, 334-386, 1953. 



6. Benoit, J. and I. Assenmacher, /. Physiol. (Paris) 47, 427-567, 1955. 



7. Benoit, J. and I. Assenmacher, Recent Prog. Hormone Res. 15, 143-164, 1959. 



8. Donovan, B. T. and J. J. van der Werff ten Bosch, /. Physiol. 147, 78-92, 1959. 



9. Donovan, B. T. and J. J. van der Werff ten Bosch, /. Physiol. 147, 93-108, 1959. 



10. Everett, J. W., Anat. Rec. 109, 291, 1951. 



11. Everett, J. W. and C. H. Sawyer, Endocrinology 47, 198-218, 1950. 



12. Forbes, T. R. and C. W. Hooker, Endocrinology 61, 281-286, 1957. 



13. FRAPS, R. M., Anat. Rec. 87, 443, 1943. 



14. FRAPS, R. M., Anat. Rec. 96, 573-574, 1946. 



15. FRAPS, R. M., Proc. Natl. Acad. Sci. U.S. 40, 348-356, 1954. 



16. FRAPS, R. M., Memoirs Soc. Endocrinol. No. 4, 205-219, 1955. 



17. FRAPS, R. M., in Progress in the Physiology of Farm Animals, vol. 2 (Edited by John 



Hammond), pp. 661-740. Butterworths Scientific Publications, London, 1955. 



18. FRAPS, R. M., in Photoperiodism and Related Phenomena in Plants and Animals (Edited 



by R. B. Withrow), pp. 767-785, Publ. No. 55, Am. Assoc. Adv. Sci., Washington, 

 D.C., 1959. 



19. FRAPS, R. M. and J. F. Case., Proc. Soc. Exp. Biol, and Med. 82, 167-171, 1953 



20. FRAPS, R. M. and M. H. Conner, Nature 174, 1148-1149, 1954. 



21. FRAPS, R. M. and A. Dury, Anat. Rec. 84, 453, 1942. 



22. FRAPS, R. M. and A. Dury, Anat. Rec. 84, 521-522, 1942. 



23. FRAPS, R. M. and A. Dury, Anat. Rec. 87, AA2-AAZ, 1943. 



24. FRAPS, R. M. and A. Dury, Proc. Soc. Exp. Biol, and Med. 52, 140-142, 1943. 



25. FRAPS, R. M. and H. L. Fevold, Proc. Soc. Exp. Biol, and Med. 90, 440-446, 1955 



26. FRAPS, R. M., H. L. Fevold and B. H. Neher, Anat. Rec. 99, 571-572, 1947. 



27. FRAPS, R. M., C. W. Hooker and T. R. Forbes, Science 108, 86-87, 1948. 



28. FRAPS, R. M. and G. M. Riley, Proc. Soc. Exp. Biol, and Med. 49, 253-257, 1942. 



29. Green, J. D., Amer. J. Anat. 88, 225-312, 1951. 



30. Green, J. D. and G. W. Harris, /. Endocrinol. 5(3), 136-146, 1947. 



31. Harris, G. W., Physiol. Rev. 28, 139-179, 1948. 



32. Harris, G. W., Monographs Physiol. Soc, No. 3. Edward Arnold, London, 1955. 



33. Heywang, B. W., Poid. Sci. 17, 240-247, 1938. 



34. Hooker, C. W. and T. R. Forbes, Endocrinology 41, 158-159, 1947. 



35. Huston, T. M. and A. V. Nalbandov, Endocrinology 52, 149-156, 1953. 



36. HuTT, F. B., K. Goodwin and W. D. Urban, Cornell Vet. 46, 257-273, 1956. 



37. Lacassagne, L., Annales de Zootech. 5, 335-362, 1956. 



38. Lanson, R. K., Unpublished Ph.D. thesis. Rutgers University, New Brunswick 



New Jersey, 1959. 



