What is the name of the soft cartilage tips on the dorsal side of ribs that ossify as they age?

The soft cartilage tips located on the dorsal side of the ribs are referred to as "buttons." As animals age, these cartilage tips undergo a process of ossification, where they transform from cartilage to bone. This process is significant in the context of skeletal development and is particularly important for understanding the maturity and structural integrity of ribcages in various species. The term "buttons" specifically highlights their rounded, soft nature before they ossify, distinguishing them from other anatomical structures that may have similar characteristics. The other terms do not accurately represent this specific feature of the ribs.