from the following, and supported by eg. Schwalbe's website, why do size equivalents go like this? :
40-622 = 700x40
38-622 = 700x38
37-622 = 700x35
32-622 = 700x32
25-622 = 700x25

etc.. ie. why does only the 37-622 tire have a different width when in the 700x## sizing (French sizing) of 35mm..? It only came up because I had ordered some 700x35 tires, and had a momentary concern when the box was labelled 37-622. I thought I had a return possibly on my hands.