Australian logrunner one of only three species within the single Orthonyx genus; the other two are the chowcilla ("Orthonyx spaldingii") from northern Queensland and the New Guinean logrunner ("Orthonyx novaeguineae") from Papua New Guinea. Logrunners as a group are characterised within their group by their distinctive tail feathers where the rachis (or central shafts) of the tail feathers protrude and are stiffened. The broad tail of the bird is less than four inches (10 cm) in length and the strong protruding rachis at the ends of the tail feathers are almost void of the usual barbs, giving the feather the appearance of
Rachis achieved pachytene and are attached to the walls of the gonadal tube. The rachis is filled with cytoplasm. In plants, a "rachis" is the main axis of a compound structure. It can be the main stem of a compound leaf, such as in "Acacia" or ferns, or the main, flower-bearing portion of an inflorescence above a supporting peduncle. A ripe head of wild-type wheat is easily shattered into dispersal units when touched or blown by the wind. A series of layers forms that divides the rachis into dispersal units consisting of a small group of flowers (a single spikelet) attached