Oh good grief. I knew I had 5 extra chicks, just due to the numbers, but had no idea what. Today when I was moving the box they came in I finally noticed a label on the side of the box. They'd originally printed each breed and the number. A couple numbers had been crossed off and a new number written by hand. Well okay then. My "extra babies" are; 2 Barred Rocks, 1 Silver Laced Wyandotte and 2 Speckled Sussex. Hopefully in the next day or 2 while the chicks are still tiny I can sort them by breed, band them and take their group pictures.
They hatched Wednesday, arrived Friday and now, after 2 full days with me, all 38 are alive, no leg problems and they're all peeping, eating and drinking. Fingers crossed this will continue.