Albert Marth discovered NGC 3641 = m 220 on 22 Mar 1865 and noted "F, vS, alm stell." His position matches UGC 6370. Wilhelm Tempel independently found this galaxy in 1876 and reported NGC 3641 in list I-34 as "Small and faint, Class III; NGC 3640 is 2' south."

400/500mm - 17.5" (2/8/91): faint, very small, round, faint stellar nucleus. Forms a close pair with bright NGC 3640 2.6' NNW.

600/800mm - 24" (5/20/20): at 375x; between pretty faint and moderately bright, round, 40" diameter, sharp concentration with a small bright nucleus. The halo seems more extensive to the south of the nucleus. Located 2.6' SSE of the center of much brighter and larger NGC 3640.

Notes by Steve Gottlieb