William Herschel discovered NGC 3733 = H III-771 on 14 Apr 1789 (sweep 920) and recorded "eF, S, irr E. On account of the brightness of the foregoing star which was in the field of view with it; I had nearly overlooked it. His position matches UGC 6554.

400/500mm - 17.5" (3/19/88): very faint, moderately large, elongated 2:1 ~N-S, very diffuse. Located 4' N of mag 5.6 SAO 28064 which detracts from viewing! Located within a large galaxy group including NGC 3738 21' SSE and NGC 3737 8' NE. NGC 3733 is not a member of AGC 1318, but rather the NGC 3898 group = LGG 250 (UMa NED2 group).

Notes by Steve Gottlieb