This paper provides the synonymy for the 13 species of Eschscholzia that I recognize. The only hope of understanding the genus lies in the living plants, and old collections and old descriptions should be used only as long as they are helpful and be ignored the moment they become confusing. Nevertheless, a reasonably coherent synonymy may eliminate needless toil for future students of the genus. By perusal of the descriptions and in some cases examination of the types I have been able to assign most of the epithets.

  1. Eschscholzia californica Chamisso in Nees von Esenbeck, Horae Physicae Berolinenses 73. 1820.
    E. californica ssp. californica.
    E. californica ssp. mexicana (Greene) C. Clark, Syst. Bot. 3:xxx. 1978.

  2. Eschscholzia caespitosa Bentham, Trans. Hort. Soc. Ser. 11 1:408. 1835.

  3. Eschscholzia parishii Greene, Bull. California Acad. Sci. 1:183. 1885.

  4. Eschscholzia covillei Greene, Pittonia 5:275. 1905

  5. Eschscholzia minutiflora S. Watson, Proc. Amer. Acad. Arts Sci. 11:122. 1876.

  6. Eschscholzia glyptosperma Greene, Bull. California Acad. Sci. 1:70. 1885.

  7. Eschscholzia lemmonii Greene, West Amer. Sci. 3:157. 1887.

  8. Eschscholzia hypecoides Bentham, Trans. Hort. Soc. Ser. 11, 1:408. 1835.

  9. Eschscholzia rhombipetala Greene, Bull. California Acad. Sci. 1:71. 1885.

  10. Eschscholzia lobbii Greene, Pittonia 5:290. 1905.

  11. Eschscholzia ramosa (Greene) Greene, Bull. Torrey Bot. Club 13:217. 1886.

  12. Eschscholzia elegans Greene, Bull. California Acad. Sci. 1:182. 1885.

  13. Eschscholzia palmeri Rose, Contr. Nat. Herb. 1:23.1890.

SPECIES INCERTAE SEDIS

Both these species, from the single collection Palmer 794, by their desciptions resemble somewhat E. californica, but the location is nearly 250 km south of the southernmost known populations of E. californica in Baja California. The location is even slightly south and west of the known distribution of E. minutiflora, and the descriptions do not match that species at all. I visited the region in the spring of 1978, which was a year of exceptional wildflower displays, and saw no Eschscholzias. If the plants are indeed E. californica, they may be relicts of a more southern full-glacial distribution.

In description this species somewhat resembles E. mexicana. Nevertheless, Munz (1959) included it in E. glyptosperma, although the seeds are not described as resembling the latter species at all. Plants of E. parishii have been found with the same cartilaginous ring around the hypanthium as E. paupercula, so until I can see the type I am unwilling to assign this species.

This species, which could answer to E. caespitosa or even E. californica, was collected near Malheur Lake in Oregon, nearly 200 km from the nearest populations of either of these species and well out of range for Eschscholzia as a genus.