Here you can (eventually) find a picture of each monster's egg.
(I will replace the smaller images to bigger ones as soon as I get higher quality screenshots taken or sent to me. If you have an egg in your Hatchery right now that you don't find on this chart, please zoom in on the Hatchery as close as you can and take a screenshot. Email the screenshot to address: email@example.com , and I will do the rest.)
Click the image below to view the chart in full size.