Connor Fitzpatrick wrote today's entry:
Commonly known as cream cups, Platystemon californicus is a wind-pollinated plant in the Papaveraceae with a distribution that stretches from northern Mexico up the Pacific coast into Oregon. The description of Platystemon californicus from eFloras reflects the extreme variety found in nearly all morphological characters:
Plants 0.3-3 dm, pilose or hirsute, sometimes glabrate. Leaves 10-90 × 1.7-8.1 mm; blade broadly linear; margins entire; apex rounded to long-acute. Inflorescences: peduncle 3.4-25.8 cm; bud globose to ovoid-cylindric. Flowers: petals white to cream colored, sometimes with yellow tip and/or base, rarely gold overall, sometimes tinged red in age, narrowly ovate to obovate, 6-19 × 3.5-16 mm, apex acute to rounded; ovary cylindric to oblong-ellipsoid; stigmas linear, margin revolute. Capsules ellipsoid, to 1.6 cm. Seeds black, shining, smooth. 2 n = 12 (plus occasional supernumerary chromosomes)
In Correlation of Morphological Variation in Platystemon californicus (Papaveraceae) with Flower Color and Geography (only the abstract is publicly available), Hannan writes that at one point 57 different species were included in what is now described as a single species, Platystemon californicus. Hannan had found that flower colours were probably under rigid genetic control and that morphological characters were not indicative of a particular flower colour or geography, and so could not be used as reliable taxonomic descriptions. The CalPhotos photo database has a good collection of images depicting what eFloras calls ecotypic variation.