Handwritten letter from Jessie Jacobs Muller Offermann to Carlos Offermann with envelope and enclosed typed letter from Jessie to G. Gokham, Chief of the Consular Division of the Embassy of the Union of Soviet Socialists Republic.

Handwritten picture postcard from H.J. Muller, N. Timofeeff-Ressovsky, and Dorrthee to David.

Handwritten picture postcard from H.J. Muller to David Muller.

Handwritten letter from H.J. Muller to David Muller with envelope and enclosed typed letter from Dick Marsh to David Muller.

Handwritten letter from H.J. Muller to David Muller with envelope.

Handwritten letter from H.J. Muller to David Muller with envelope.

Handwritten picture postcard of Woodshole from H.J. Muller to David Muller and Jessier Jacobs Muller Offermann.

Handwritten letter from H.J. Muller to David Muller with envelope.

Handwritten letter from Jessie Jacobs Muller Offermann to David Muller with envelope.

Handwritten notebooks and loose pages for a planned genetics text by Hermann J. Muller and Edgar Altenberg while in graduate school at Columbia University, 1912, which was unpublished. "This is the original notebook of Muller's... for the projected…