The Plank Road Panther has become one world-travelin' cat. If he is indeed just one.

We've done several stories about this mysterious, zoo-sized, catlike animal, usually described as black or dark gray, that many people have seen in the area between Plato Center and Pingree Grove.

But the feline has changed habits. From last summer through January, it was seen only in the area between Plato and Pingree. Then suddenly, people in that area stopped seeing it. But people all over the far-northwest suburbs began seeing a similar cat. We have mentioned some of these incidents in The Courier-News before; others we haven't.

Those who feel safe from such critters in the heart of town may not want to hear this one: Toward the end of March, reader Sue Lucio was driving along Big Timber Road near McLean Boulevard, just a few hundred feet from the Big Timber Metra station. Suddenly, she says, "What looked like a large cat ran out in front of my car. ... It was tan in color and ran fast across the road. Dashed into the bushes by the railroad track, right by the Sparkle Glass Co."

An even more-definitive, right-in-town sighting report came from reader Chuck Lane. Lane said he was walking his dog along Route 72 at the railroad crossing in Gilberts on March 26. Suddenly, they encountered an all-black cat -- "for sure not a house cat, looks to be 40 to 50 pounds," Lane says. "Our dog chased it and it stopped dead in its tracks and made an awful sound, then proceeded down the railroad track."

We already told you how on March 23, employees of the Elgin Target store spotted a 7-foot-long black cat on the other side of a cornfield behind the store, and how reader Michelle Jurss and two others saw a dark-colored, long-tailed cat near Route 59 and Stearns Road at Bartlett on March 5.

Reader Jim Kucera wrote that he saw a similar animal a couple of years ago, on Coombs Road near Burnidge Forest Preserve west of Elgin.

These incidents are far-flung. But one common thread is railroad tracks. The sightings in Gilberts and at Big Timber and McLean occurred on the same rail line, a few days apart. Even the Bartlett sightings occurred close to the same rail line that runs through faraway Plato Center. The sighting near Target was far from any railroad, but close to a creek that leads toward Plato.

But we still have no photo of the mystery beast except one blurry image taken by a hunter's motion-activated "deer camera" in November. If you see the beast, please, please, please grab your cell phone and snap a picture.

The latest twist came a couple of weeks ago, when reports of cougar sightings began coming in from way off in central DuPage County. Could it be our old buddy?

Or could northeastern Illinois have a whole population of cougar-like animals that biologists refuse to acknowledge?