Christmas boobook lores and throat, yellow eyes, legs and feet. It is approximately 26–29 cm in length and 130-190 grams in weight with the female slightly larger than the male. The double-noted hoot, "boo-book," has a clucking quality with the second note usually lower in pitch. The begging call of juveniles is a high-pitched trill. Vocalisations are similar to those described for the Southern Boobook "N. novaeseelandiae" and include individual variation in advertisement calls. This may be useful in estimating owl densities as radio-tracking can be impractical in some terrains. A recording, courtesy of Richard Hill and Owl Pages http://www.owlpages.com/sounds/Ninox-natalis-2.mp3 Its natural
Anatomical terms of bone or Superior pubic ramus. Ramus may also be used to refer to nerves, such as the ramus communicans. A "facet" refers to a small, flattened articular surface. A "line" refers to a long, thin projection, often with a rough surface. "Ridge" and "crest" refer to a long, narrow line. Unlike many words used to describe anatomical terms, the word "ridge" is derived from Old English. A "spine", as well as referring to the spinal cord, may be used to describe a relatively long, thin projection or bump. These terms are used to describe bony protuberances in specific parts of the