John Herschel discovered NGC 3261 = h3258 on 15 Mar 1836 and recorded "F; S; R: 15"; entangled among 2 or 3 stars, but is certainly a nebula." His position matches ESO 263-040.

300/350mm - 13.1" (2/18/04 - Costa Rica): fairly faint, moderately large, elongated 2:1 ~WSW-ENE, 1.4'x0.7', weak concentration. Bracketed between two mag 12 stars at the SW and NE ends (separation 2.6'). Located 4' SE of a mag 10 star in a rich Vela starfield. NGC 3261 is in a subgroup of the Hydra-Centaurus Supercluster (brightest member NGC 3256) and is 9° south of the rich Antlia Cluster (but has the same redshift).

Notes by Steve Gottlieb