and as soon as possible send you a list of species and a determination of the geologic age.  I will also return to you duplicates as you suggest and where that cannot be done will substitute from duplicates in our other Montana collections.  Will this be satisfactory?  By the same mail which carries this letter I will send a separtate from the Yellowstone Park Monograph, in which the fauna of the Madison limestone is described and to some extent figured.  The Madison fauna is widely distributed in Montana and this report may help you in indentfying many of the Carboniferous fossils you are likely to collect.  Your kind offer to show me localities etc. is noted with grateful pleasure.  I shall probably work in the west this summer but it is almost too early to plan anything definite.  I fear, however, that I cannot join you.



Georgost Grity

Asst. Geol. & Asst. Pal.



P.S. If I can assist in identifying upper paleogoic fossils in connection with your college work, I will be glad to do so.