I often take 'screengrabs' of webpages, which results in a png. file which is very long compared to its width.

I often need and want to print these to paper so that the image is as wide at the width of the page (excluding margins), and therefore because of its length will extend over two or more pages. (Please note that this is nothing to do with "bleeding" the edges - I am happy to have small margins).

But all the software I have tried eg. Geegie, will only print the whole image on one page, which makes it impossible to read even with a microscope.

What linux software is there that can print images in the way described above?

(Printing directly from the webpage often does not work as the result may omit vital parts of the page).

Thanks.

Since it's a png, you can use gimp to print it. You might find cutting the image up works better, which you can do in gimp. Just a little math is needed, depending on how. Assuming that gimp doesn't have a fit to width, or the printer settings has that (I've seen it somewhere).

8.5" x 11" (letter or whatever sized in portrait).

600 dpi (dots per inch)

5100px wide (8.5")
6600px tall (11")

per page. Probably not your image size, but you can resize it. And type in manually the px values in the cut dialog. Many roads to rome.