Stone Trust Corporation.

Sigma Delta Chi Society was founded by students of the Yale Sheffield Scientific School in 1863. Not wanting to be considered a fraternity, the society changed it name to the Book and Snake Society in the late 1870s. Members who lived in the society residence, or "Cloister", become the Cloister Club. Graduates and honorary members of Book and Snake were also members of the Cloister Club. In 1876 the society incorporated as the Stone Trust Corporation. The Book and Snake converted to a senior society in 1933.

From the description of Stone Trust Corporation, Yale University, records 1850-2007 (inclusive). (Unknown). WorldCat record id: 702163778

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