Which bone is not present in all five fingers?

The hand has 27 bones what is not including the sesamoid bone, the number of which varies between people, 14 of which are the phalanges of the fingers and thumb. The metacarpal bones connect the fingers and the carpal bones of the wrist.

The bones of the fingers. Each finger has three phalanges, except for the thumb, which has two. The phalanges are the bones of the fingers. The thumb has a proximal and distal phalanx, while the rest of the digits have proximal, middle and distal phalanges. so the thumb dont have the middle phalanges