Elbow Cousins

My friend Marge has discovered that she and I may be (as she puts it) "elbow cousins." The details aren't important: what intrigues me is the phrase, which I don't think I had heard before. But it turns out to have an ancient and distinguished lineage. Here is a discussion from perhaps the greatest of all English historians:

Now here again is a curious likeness to old English law. The payment of the bulk of the wergild was preceded in England by the payment of a sum to the nearest relatives of the slain. This was the heals-fang; in the Latin versions “apprehensio colli,” the taking of the neck. “Heals-fang belongs to the children, brothers, and paternal uncles; that money belongs to no kinsman, except to those within the joint (binnan cneowe).” Our older commentators supposed that heals-fang had something to do with the pillory. But Dr Schmid has ingeniously suggested that it is connected with a mode of representing the degrees of relationship by reference to the various limbs of the human body which was well known among the Germans . It is the portion taken by those who “stand in the neck,” those who are within the joint (binnan cneowe); more distant relations “elbow cousins,” “nail cousins,” and the like have no share. However, there are many differences between the heals-fang and the saraad, and we by no means intend to suggest that the resemblance between Welsh and English law is due to any survival of British customs in England, or to any influence of English upon Welsh law.

--Frederic William Maitland, The Laws of Wales--The Kindred and the Blood Feud,
The Collected Papers of Frederic William Maitland, vol. 1 [1911]
(reprinted here)