HTML Table Diappearing Images in Row 5

I have been using the same gallery format for about 10 years now and am having a problem not previously encountered. gallery row 5 only shows alternate text.

Apparently the code is being read correctly but the images are not being found…
Not Found
The requested URL /Chessie/pix/r5c1.jpg was not found on this server.
Additionally, a 404 Not Found error was encountered while trying to use an ErrorDocument to handle the request.

The images in the previous 4 rows show up just fine. Is there a limit?
Anybody got any ideas? Thanks oodles.

Rename the files so the extension is jpg instead of JPG

Oh! Thank you. I had looked but did not see. Or I saw what I knew was supposed to be there. All happy now.