Animal illustrations for a children's book

Illustrations are needed for a children's book. The book is a series of riddles about animals. Each of the riddles mentions the animal and its habitat. For each riddle, I want one illustration that depicts the animal in its habitat. For example, one of the riddles is "I run. I play in the open backyard. Cats sleep but not me. Who am I?" The illustration will be of a dog in an open backyard. I have 15 riddles plus one cover page. The cover page will be one illustration that contains all the fifteen animals. This will be a wrap around cover. So the cover page will be roughly twice as long as the animal illustrations. I am not after any particular styles of illustrations. As long as they look good, and are suitable for a children's book, I'll consider it. All illustrations will be in color. All illustrations will be submitted in adobe illustrator format and also high quality jpg files. Choose paper size that shows your work best. Bidders should provide me with a simple illustration that shows me the style that they will use for the work, on a canvas the same size as the book page they will use in illustrating. A bid without a link to an example will be ignored. The payment for the work will be $200. If the book gets published, the illustrator will be properly credited. No further compensation beyond the $200 will be given.