At the truck stop diner Mulder and Scully stop at with the two girls, a key is needed to enter the restrooms. However, the doors on the restrooms have no outer locks or keyholes.
When Mulder first picks up his soda which has been spiked with foxglove, the spilled green foxglove liquid is vaguely visible around the bottom of the cup, positioned just behind the two rivets on the table from the camera's perspective. When he returns to pick up his keys, however, the green spill has moved to a different spot in front of the rivets. It is also a much darker green color, and has an almost crystalline appearance, whereas it had previously been a light green-colored liquid.
When the second girl was abducted, Scully reports to the cop that Sally fled in a light blue '93 Corolla. But when Sally gets to the motel in Point Reyes, she arrives in a dark blue Pontiac Bonneville.
The girls say they cultivated the foxglove themselves. The powdered foxglove is then kept in a vial. The powder looks very green, like peas. Real dried foxglove looks brownish with a tint of whatever colour the flower was (usually purple).
A Canadian flag is reflected in the "NO VACANCY" sign outside the motel that is supposed to be situated 40 miles north of San Fransisco.
Highway 49 in California is nowhere near Point Reyes.
Part of the plot line takes place in Point Reyes, yet Mulder refers to this town as Port Reyes.
The doctor's name is "Dr. Sally Kendrick," and most characters refer to her by that name, including Dr Kendrick herself in the video seen at the clinic, and Scully when she is reviewing the patient history form. But when discussing the video with Mulder, Scully calls her "Kendricks".