Regular Meeting, April 18th, 1864.
Dr. Trask in the Chair.
Present, nine members.
W. S. Brigham and Horace Mann were elected corresponding members, being about to proceed to the Sandwich Islands to make a thorough scientific exploration, under the auspices of the Boston Society of Natural History.
The name of Mr. Louis Janin, elected in 1861 but accidentally omitted from the list of members, was directed to be published in the proceedings.
Donations to the Cabinet: About two hundred specimens of rocks and ores from Humboldt River District, by Mr. Highton.
Dr. Trask presented the following paper: