February 23, 1942
Dear Dr. Demerec:
I was genuinely astonished by your invitation to participate in the Symposium on "Hormones in Development" for I certainly can lay no claim to being a worker in this field.  Before deciding whether to accept your offer it is therefore necessary for me to have a clearer idea of what you would like to have me discuss.  On the one hand Thimann is listed to talk about Microorganisms.  Will this include the Protozoa?  Will it include the work of Moewus on Chlamydomonas "sex-stuffs"?  On the other hand, Ephrussi is down for the Invertebrates.  Since a distinction is made between Invertebrates and Lower Invertebrates, I presume Ephrussi proposes to discuss the Insects.  Will he also take over the Crustacea and the recent work of Tyler and of Hartmann and collaborators on the fertilization "gamones" in Echinoderms and Annelids?
If Thimann and Ephrussi do include the matters I have mentioned, as it would seem proper for them to do, then what is left for me consists namely of three subjects: (1) the effects of Vertebrate hormones on lower Invertebrates; (2) the existence in lower Invertebrates of substances which act on Vertebrates like Vertebrate  hormones; and (3) some observations suggesting normal hormone action, -- especially sex hormones -- within some of the lower Invertebrates.  On none of these matters am I well informed and they have recently been reviewed fully in book form by Hamstrom (1939); I therefore wonder whether it would be worth while to present a paper on them at all, and particularly by one who is so little acquainted with them as I am.
The only phase of the subject allotted to me that I feel I already know pretty well is the subject of "sex-stuffs" in Chylamydomonas and possibly in ciliates (though practically nothing is known about the latter).  I have already reviewed this subject (up to 1939) in my chapter in Calkins' book on "Protozoa in Biological Research".  But I am sure Thimann, who has also reviewed this for Chronica Botanica, could do it better than I could.
I hope you understand the quandary I am in and will let me know more precisely concerning the possible overlaps with Ephrussi and Thimann.  I do appreciate being invited and would gladly accept if I felt I had a contribution to make; but it does look to me now as if I have none.  However, I shall know better what to say when I hear further from you.
With all good wishes,
Yours,
T.M. Sonneborn