HCA: Hermit Crab Association

Hi guys! When you measure shell openings you do it at the widest point right? Normally horizontally across the opening? Cause I just received an order of shells from Richards and it seems like he measured the shells at the narrowest point, they are quite a bit too large.

In July I ordered 5 shells from Richard's; based on my measurements, 3 of them were within the specs stated on the web page and 2 of them were too large. I was looking for a range anyway, and I included a comment on my order like "try not to give me any two of the same size please" (because I ordered some in the same species/size class under the assumption there would be variation). So possibly he went a little "overboard" in terms of trying to vary the sizes in my order. But, based on your experience I wonder if there are other issues.