It is to me a most distasteful task to take part publicly in the “Colias” controversy between Mr. Edwards and Dr. Hagen, as I was an invited guest of Dr. Hagen on the trip to Washington Territory, where the events took place which have given rise to the discussion; but in the interest of science, which seeks nothing but the truth, it seems as though the time had come when I ought to state in a concise manner what I know of the whole matter. I have been cut off from all my books for the last five months, while travelling from place to place, or this letter would have been written earlier. I did not know till quite recently the phase to which the controversy had arrived. Probably the best thing I can do is to state the manner in which our party was organized, and the manner in which our collecting was done.

The party consisted of Dr. Hagen, and his assistant, Samuel Henshaw. In San Francisco I was invited to join it, and did so.