With a single sentence, Silliman unintentionally offended Hitchcock, who interpreted him as implying that Deane was the true discoverer of the fossil footprints, and he (Hitchcock) a mere follower.
"It is worthy of remark, that the trifid tracks and impressions on the new red sandstone of the valley of the Connecticut, so zealously explored by Dr. James Deane of Greenfield, and both explored, and figured and described by Prof. Hitchcock, leave no reasonable doubt, that they are, at least in part, due to the feet of birds—some of them of colossal dimension. (Reptiles would seem more probable, but many of the tracks appear decidedly those of birds.)"
From American Journal of Science, Vol. 43 (October 1842), page 241.