Waist is measured from side seam to side seam across the front across the elastic band ( double to get the circumference), and then it measured across while the waist band is stretched out ( double to get the circumference). The hips are measured from side seam to side seam across the front at the widest point. The length is measured from the waist band down to the hem. The inseam is measured from the crotch seam straight down to the hem.
 
In our most recent reorder, the pants are about 2"-3" longer. Pants shown on the model were the cropped length. We have one cropped length left in a medium in oyster.
The navy does run slightly smaller.
Oyster: avaibale in medium
Small: waist is 13" (26" around) and will stretch to 21" (42" around), hips are 21.5" (43" around), length is 32", inseam is 21.5"
Cropped Medium: waist is 14" (28" around) and will stretch to 22" (44" around), hips are 22" (44" around), length is 32.5" , inseam is 22"
Long Medium: waist is 14" (28" around) and will stretch to 22" (44" around), hips are 22" (44" around), length is 36" , inseam is 23.5"
Navy: small 
Small: waist is 12" (24" around) and will stretch to 20" (40" around), hips are 21" (42" around), length is 35.5", inseam is 23.5"