**Table 6:** Average colours of the host galaxies^a.
The sample	U-B	B-V	B-R	R-H	B-H
(1)	(2)	(3)	(4)	(5)	(6)
BL Lacs (this work)	$0.3\pm0.4$	$0.8\pm0.2$	$1.2\pm0.5$	$2.2\pm0.4$	$3.5\pm0.5$
Quasars (Jahnke et al. 2004)		$0.5\pm0.1$	$1.1\pm0.1$	$1.9\pm0.2$	$2.9\pm0.3$
RGs (Govoni et al. 2000)			$1.4\pm0.2$
Ellipticals (Peletier et al. 1990)	$0.6\pm0.1$		$1.6\pm0.1$
Ellipticals (Bower et al. 1992)					$3.8\pm0.2$
Ellipticals (Colbert et al. 2001)			$1.5\pm0.2$
Ellipticals (Fukugita & Ichikawa 1995)		1.0	1.6
Ellipticals (Fioc & Rocca-Volmerange 1999)				2.2	3.8
Spirals (Sb) (Fioc & Rocca-Volmerange 1999; Fukugita & Ichikawa 1995)		0.7	1.2	2.1	3.3

^aColumn (1) gives the sample; and Cols. (2)-(6) the average U-B, B-V, B-R, R-H and B-H colour, respectively.