2 Inches Long. This is good size. It is quite portable, large enough to feel solid. Sturdy. This is likely the best size for your Casting Collection.
Inspired by the Spine, The Rib Cage, The Crab, The Scorpion and The Spider. The ribs spin on the central spine, so that they can fall in unique ways to deliver different messages. There are three or four primary positions that the overall form might take, when Cast. Walking (Alive). Inverted (Submissive/Dead), Mixed and Standing (Rare). And then you have the orientation of the form, when it is Cast. And then you have its relationship to the other Artifacts (Houses) in the Casting/Reading
Consider how this form can interact with the other Houses in your Casting/Reading.
Notice that the head and the tail are different in thier orientation from each other. They are rotated 90 degrees (ish) to each other. One can be considered the head, and the other the tail. Consider if the head or tail is pointing towards another Bone House. Or touching one. Or are the head and the tail so similar, that this form could point two directions, or no directions?
Is the overall form overlaping another House? Did it land reversed, and another House landed in its arms? Are one or more of its legs, interacting with another House? Is it arced over another House, as if protecting it? or Trapping it?
Look at the individual ribs/legs. Each one is different from the others. Some are smaller overall. Some arc more. Some raise up. One has something tucked close to the spine, as if protecting it. One seems to be broken and yet is still solid - perhaps reformed, after a break. etc.
Part of "Housekeeping" for your Bone Houses includes the study and/or meditation of the House. Get to know it. Consider what emotions it suggests. Will your Bone House hold a Spirit? Or will it represent a collection of ideas? Which Spirit? Which Ideas?
Does the name of this bone - Ishbo - suggest something to you? Or should you rename it when it joins your collection?