If you look carefully at the orbit of Mercury you can see that it is elliptical. Pluto is also somewhat elliptical, which is hard to tell directly but given away by the fact that it crosses inside the Neptune orbit (this is also mentioned in the text). If you compare the distance between Earth and Mars around the "AST" in "Mars Crossing Asteroids" and around "Fortuna" you can see that the Mars orbit is somewhat elliptical. All the other planets orbits are much closer to circular and you can not see the eccentricity by eye.
Just to add the data, Mercury with 0.206 and Pluto with 0.248 are the only ones with a clearly visible eccentricity, the rest of the planets have eccentricity <0.1. For instance our Earth has 0.017 eccentricity, with an perihelion of 0.98 AU and an aphelion of 1.02 AU, so quite difficult to tell visually.
