Abstract: A construction member having two side wall faces and an adjacent end face, one of the faces having a trough extending therein, a ramp for gripping by a clamp, functioning as a dovetail mortise, formed adjacent the trough bottom and extending along a wall of the trough, and a protrusion with respect to the trough bottom formed of a trough wall, a portion of said one face, another face and the ramp, the protrusion and the trough having the configuration of a modified half dovetail tenon rail.A construction member being an assembly of two juxtaposed panels, each panel having side faces as opposite wall surfaces and end faces forming the peripheral edge of the two panels, each end face forming the peripheral edge having a modified half dovetail tenon rail, the two rails being in an allochiral relationship and forming a substantially full dovetail tenon rail, and clamps, functioning as dovetail mortises, having gripping ends in engagement with respective tenon rails in each panel securing the two panels together.