(Fullerton,..George	and Cattell,James Me
ieen.)
On the perception of small differences. With
special reference to the extent, force and time
of movement. By the editors.
8:o Philadephia 1892.
(Publications of the university of Pennsylva-
nia. Philosophical series. Edited by George
Stuart Fplle^tp?! and James He Keen Cattehb^o.2
May 189^)	—

. (Fullerton.... Ge orge. Stuart and C att ell, James Me
Keen.)
On the perception of small differences. With
special reference to the extent, force and time
of movement. By the editors.
8:o Philadephia 1892.
(Publications of the university of Pennsylva-
nia. Philosophical series. Edited by George
Stuart Fullerton and James Mc Keen Cattel]No.2
May 1892.)	Ri